CINXE.COM

Project Y - Wikipedia

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Project Y - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"ae6dfc25-7900-455b-8b51-e7db1cbd5282","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Project_Y","wgTitle":"Project Y","wgCurRevisionId":1257082060,"wgRevisionId":1257082060,"wgArticleId":51053117,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Pages using gadget WikiMiniAtlas","Articles using NRISref without a reference number","Articles with short description","Short description matches Wikidata","Featured articles","Use dmy dates from October 2019","Coordinates on Wikidata","NRHP infobox with nocat","Pages using multiple image with auto scaled images","Code names","Former nuclear research institutes","History of the Manhattan Project","Los Alamos, New Mexico","Manhattan Project sites","Military history of New Mexico", "Military in New Mexico","Military projects of the United States"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Project_Y","wgRelevantArticleId":51053117,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":100000,"wgCoordinates":{"lat":35.88055555555555,"lon":-106.30388888888889},"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage" ,"wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q27832090","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=[ "ext.cite.ux-enhancements","mediawiki.page.media","ext.scribunto.logs","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.gadget.WikiMiniAtlas","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&amp;modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&amp;only=styles&amp;skin=vector-2022"> <script async="" src="/w/load.php?lang=en&amp;modules=startup&amp;only=scripts&amp;raw=1&amp;skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&amp;modules=site.styles&amp;only=styles&amp;skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/1200px-Army-Navy_E_Award.jpg"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="815"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/800px-Army-Navy_E_Award.jpg"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="544"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/640px-Army-Navy_E_Award.jpg"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="435"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Project Y - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Project_Y"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Project_Y&amp;action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Project_Y"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&amp;feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Project_Y rootpage-Project_Y skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page&#039;s font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&amp;utm_medium=sidebar&amp;utm_campaign=C13_en.wikipedia.org&amp;uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&amp;returnto=Project+Y" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&amp;returnto=Project+Y" title="You&#039;re encouraged to log in; however, it&#039;s not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&amp;utm_medium=sidebar&amp;utm_campaign=C13_en.wikipedia.org&amp;uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&amp;returnto=Project+Y" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&amp;returnto=Project+Y" title="You&#039;re encouraged to log in; however, it&#039;s not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"><!-- CentralNotice --></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Origins" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Origins"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Origins</span> </div> </a> <button aria-controls="toc-Origins-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Origins subsection</span> </button> <ul id="toc-Origins-sublist" class="vector-toc-list"> <li id="toc-Nuclear_fission_and_atomic_bombs" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Nuclear_fission_and_atomic_bombs"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Nuclear fission and atomic bombs</span> </div> </a> <ul id="toc-Nuclear_fission_and_atomic_bombs-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bomb_design_concepts" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Bomb_design_concepts"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Bomb design concepts</span> </div> </a> <ul id="toc-Bomb_design_concepts-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bomb_laboratory_concept" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Bomb_laboratory_concept"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.3</span> <span>Bomb laboratory concept</span> </div> </a> <ul id="toc-Bomb_laboratory_concept-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Site_selection" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Site_selection"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Site selection</span> </div> </a> <ul id="toc-Site_selection-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Construction" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Construction"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Construction</span> </div> </a> <ul id="toc-Construction-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Organization" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Organization"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Organization</span> </div> </a> <button aria-controls="toc-Organization-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Organization subsection</span> </button> <ul id="toc-Organization-sublist" class="vector-toc-list"> <li id="toc-Military" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Military"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Military</span> </div> </a> <ul id="toc-Military-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Civilian" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Civilian"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Civilian</span> </div> </a> <ul id="toc-Civilian-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Gun-type_weapon_design" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Gun-type_weapon_design"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Gun-type weapon design</span> </div> </a> <button aria-controls="toc-Gun-type_weapon_design-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Gun-type weapon design subsection</span> </button> <ul id="toc-Gun-type_weapon_design-sublist" class="vector-toc-list"> <li id="toc-Research" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Research"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Research</span> </div> </a> <ul id="toc-Research-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Development" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Development"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Development</span> </div> </a> <ul id="toc-Development-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Plutonium" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Plutonium"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Plutonium</span> </div> </a> <ul id="toc-Plutonium-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Implosion-type_weapon_design" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Implosion-type_weapon_design"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Implosion-type weapon design</span> </div> </a> <ul id="toc-Implosion-type_weapon_design-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Little_Boy" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Little_Boy"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Little Boy</span> </div> </a> <ul id="toc-Little_Boy-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Water_boiler" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Water_boiler"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>Water boiler</span> </div> </a> <ul id="toc-Water_boiler-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Super" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Super"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Super</span> </div> </a> <ul id="toc-Super-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Trinity" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Trinity"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>Trinity</span> </div> </a> <ul id="toc-Trinity-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Project_Alberta" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Project_Alberta"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>Project Alberta</span> </div> </a> <ul id="toc-Project_Alberta-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Health_and_safety" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Health_and_safety"> <div class="vector-toc-text"> <span class="vector-toc-numb">13</span> <span>Health and safety</span> </div> </a> <ul id="toc-Health_and_safety-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Security" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Security"> <div class="vector-toc-text"> <span class="vector-toc-numb">14</span> <span>Security</span> </div> </a> <ul id="toc-Security-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Post-war" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Post-war"> <div class="vector-toc-text"> <span class="vector-toc-numb">15</span> <span>Post-war</span> </div> </a> <ul id="toc-Post-war-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">16</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">17</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Project Y</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 11 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-11" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">11 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar badge-Q17437796 badge-featuredarticle mw-list-item" title="featured article badge"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%B4%D8%B1%D9%88%D8%B9_Y" title="مشروع Y – Arabic" lang="ar" hreflang="ar" data-title="مشروع Y" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Projekt_Y" title="Projekt Y – Estonian" lang="et" hreflang="et" data-title="Projekt Y" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%BE%D8%B1%D9%88%DA%98%D9%87_Y" title="پروژه Y – Persian" lang="fa" hreflang="fa" data-title="پروژه Y" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Projet_Y" title="Projet Y – French" lang="fr" hreflang="fr" data-title="Projet Y" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Proxecto_Y" title="Proxecto Y – Galician" lang="gl" hreflang="gl" data-title="Proxecto Y" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AA%E0%A4%B0%E0%A4%BF%E0%A4%AF%E0%A5%8B%E0%A4%9C%E0%A4%A8%E0%A4%BE_Y" title="परियोजना Y – Hindi" lang="hi" hreflang="hi" data-title="परियोजना Y" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Project_Y" title="Project Y – Indonesian" lang="id" hreflang="id" data-title="Project Y" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Project_Y" title="Project Y – Turkish" lang="tr" hreflang="tr" data-title="Project Y" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9F%D1%80%D0%BE%D1%94%D0%BA%D1%82_Y" title="Проєкт Y – Ukrainian" lang="uk" hreflang="uk" data-title="Проєкт Y" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/D%E1%BB%B1_%C3%A1n_Y" title="Dự án Y – Vietnamese" lang="vi" hreflang="vi" data-title="Dự án Y" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh badge-Q70893996 mw-list-item" title=""><a href="https://zh.wikipedia.org/wiki/Y%E8%AE%A1%E5%88%92" title="Y计划 – Chinese" lang="zh" hreflang="zh" data-title="Y计划" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q27832090#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Project_Y" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Project_Y" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Project_Y"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Project_Y&amp;action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Project_Y&amp;action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Project_Y"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Project_Y&amp;action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Project_Y&amp;action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Project_Y" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Project_Y" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Project_Y&amp;oldid=1257082060" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Project_Y&amp;action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&amp;page=Project_Y&amp;id=1257082060&amp;wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&amp;url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FProject_Y"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&amp;url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FProject_Y"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&amp;page=Project_Y&amp;action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Project_Y&amp;printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="wb-otherproject-link wb-otherproject-commons mw-list-item"><a href="https://commons.wikimedia.org/wiki/Category:Los_Alamos_National_Laboratory" hreflang="en"><span>Wikimedia Commons</span></a></li><li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q27832090" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> <div id="mw-indicator-coordinates" class="mw-indicator"><div class="mw-parser-output"><span id="coordinates"><a href="/wiki/Geographic_coordinate_system" title="Geographic coordinate system">Coordinates</a>: <style data-mw-deduplicate="TemplateStyles:r1156832818">.mw-parser-output .geo-default,.mw-parser-output .geo-dms,.mw-parser-output .geo-dec{display:inline}.mw-parser-output .geo-nondefault,.mw-parser-output .geo-multi-punct,.mw-parser-output .geo-inline-hidden{display:none}.mw-parser-output .longitude,.mw-parser-output .latitude{white-space:nowrap}</style><span class="plainlinks nourlexpansion"><a class="external text" href="https://geohack.toolforge.org/geohack.php?pagename=Project_Y&amp;params=35_52_50_N_106_18_14_W_"><span class="geo-default"><span class="geo-dms" title="Maps, aerial photos, and other data for this location"><span class="latitude">35°52′50″N</span> <span class="longitude">106°18′14″W</span></span></span><span class="geo-multi-punct">&#xfeff; / &#xfeff;</span><span class="geo-nondefault"><span class="geo-dec" title="Maps, aerial photos, and other data for this location">35.88056°N 106.30389°W</span><span style="display:none">&#xfeff; / <span class="geo">35.88056; -106.30389</span></span></span></a></span></span></div></div> <div id="mw-indicator-featured-star" class="mw-indicator"><div class="mw-parser-output"><span typeof="mw:File"><a href="/wiki/Wikipedia:Featured_articles*" title="This is a featured article. Click here for more information."><img alt="Featured article" src="//upload.wikimedia.org/wikipedia/en/thumb/e/e7/Cscr-featured.svg/20px-Cscr-featured.svg.png" decoding="async" width="20" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e7/Cscr-featured.svg/30px-Cscr-featured.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/e/e7/Cscr-featured.svg/40px-Cscr-featured.svg.png 2x" data-file-width="466" data-file-height="443" /></a></span></div></div> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Secret laboratory established by the Manhattan Project</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"Los Alamos Laboratory" redirects here. For the present-day laboratory, see <a href="/wiki/Los_Alamos_National_Laboratory" title="Los Alamos National Laboratory">Los Alamos National Laboratory</a>.</div> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vcard"><caption class="infobox-title fn org">Los Alamos Laboratory</caption><tbody><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Army-Navy_E_Award.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/220px-Army-Navy_E_Award.jpg" decoding="async" width="220" height="149" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/330px-Army-Navy_E_Award.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/87/Army-Navy_E_Award.jpg/440px-Army-Navy_E_Award.jpg 2x" data-file-width="2000" data-file-height="1359" /></a></span><div class="infobox-caption"><a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a> (left), <a href="/wiki/Leslie_Groves" title="Leslie Groves">Leslie Groves</a> (center) and <a href="/wiki/Robert_Gordon_Sproul" title="Robert Gordon Sproul">Robert Sproul</a> (right) at the ceremony to present the Los Alamos Laboratory with the <a href="/wiki/Army-Navy_%22E%22_Award" title="Army-Navy &quot;E&quot; Award">Army-Navy "E" Award</a> at the <a href="/wiki/Fuller_Lodge" class="mw-redirect" title="Fuller Lodge">Fuller Lodge</a> on 16 October 1945</div></td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em">Established</th><td class="infobox-data">1&#160;January&#160;1943<span style="display:none">&#160;(<span class="bday dtstart published updated itvstart">1943-01-01</span>)</span></td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em">Research&#160;type</th><td class="infobox-data category">Classified</td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em"><a href="/wiki/Budget" title="Budget">Budget</a></th><td class="infobox-data">$57.88 million</td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Field&#160;of research</div></th><td class="infobox-data category"><a href="/wiki/Nuclear_weapons" class="mw-redirect" title="Nuclear weapons">Nuclear weapons</a></td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em"><a href="/wiki/Director_(business)" title="Director (business)">Director</a></th><td class="infobox-data agent"><a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a><br /><a href="/wiki/Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a></td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em">Location</th><td class="infobox-data"><a href="/wiki/Los_Alamos,_New_Mexico" title="Los Alamos, New Mexico">Los Alamos</a>, New Mexico, United States<br /><span class="geo-inline"><style data-mw-deduplicate="TemplateStyles:r1156832818">.mw-parser-output .geo-default,.mw-parser-output .geo-dms,.mw-parser-output .geo-dec{display:inline}.mw-parser-output .geo-nondefault,.mw-parser-output .geo-multi-punct,.mw-parser-output .geo-inline-hidden{display:none}.mw-parser-output .longitude,.mw-parser-output .latitude{white-space:nowrap}</style><span class="plainlinks nourlexpansion"><a class="external text" href="https://geohack.toolforge.org/geohack.php?pagename=Project_Y&amp;params=35_52_50_N_106_18_14_W_"><span class="geo-default"><span class="geo-dms" title="Maps, aerial photos, and other data for this location"><span class="latitude">35°52′50″N</span> <span class="longitude">106°18′14″W</span></span></span><span class="geo-multi-punct">&#xfeff; / &#xfeff;</span><span class="geo-nondefault"><span class="geo-dec" title="Maps, aerial photos, and other data for this location">35.88056°N 106.30389°W</span><span style="display:none">&#xfeff; / <span class="geo">35.88056; -106.30389</span></span></span></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="padding-right:0.65em"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Operating agency</div></th><td class="infobox-data"><a href="/wiki/University_of_California" title="University of California">University of California</a></td></tr><tr><td colspan="2" class="infobox-full-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1257001546"></td></tr><tr><td colspan="2" class="infobox-subheader" style="padding:0; border:none;"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1257001546"></td></tr><tr><td colspan="2" class="infobox-full-data"><div class="skin-nightmode-reset-color" style="width:100%; font-size:110%; font-weight:bold;color: #202122; background: #A8EDEF; line-height:1.5">Los Alamos Scientific Laboratory</div></td></tr><tr><td colspan="2" class="infobox-full-data"><div style="width:100%; text-align:center; line-height:1.5;color: #202122; background: #A8EDEF;"><a href="/wiki/National_Register_of_Historic_Places" title="National Register of Historic Places">U.S. National Register of Historic Places</a></div></td></tr><tr><td colspan="2" class="infobox-full-data"><div style="width:100%; text-align:center; line-height:1.4; color: #202122; background: #87CEEB"><a href="/wiki/National_Historic_Landmark" title="National Historic Landmark">U.S. National Historic Landmark District</a></div></td></tr><tr style="display:none"><td colspan="2"> </td></tr><tr><td colspan="2" class="infobox-image"><div class="switcher-container"><style data-mw-deduplicate="TemplateStyles:r1238443738">.mw-parser-output .locmap .od{position:absolute}.mw-parser-output .locmap .id{position:absolute;line-height:0}.mw-parser-output .locmap .l0{font-size:0;position:absolute}.mw-parser-output .locmap .pv{line-height:110%;position:absolute;text-align:center}.mw-parser-output .locmap .pl{line-height:110%;position:absolute;top:-0.75em;text-align:right}.mw-parser-output .locmap .pr{line-height:110%;position:absolute;top:-0.75em;text-align:left}.mw-parser-output .locmap .pv>div{display:inline;padding:1px}.mw-parser-output .locmap .pl>div{display:inline;padding:1px;float:right}.mw-parser-output .locmap .pr>div{display:inline;padding:1px;float:left}@media screen{html.skin-theme-clientpref-night .mw-parser-output .od,html.skin-theme-clientpref-night .mw-parser-output .od .pv>div,html.skin-theme-clientpref-night .mw-parser-output .od .pl>div,html.skin-theme-clientpref-night .mw-parser-output .od .pr>div{background:#fff!important;color:#000!important}html.skin-theme-clientpref-night .mw-parser-output .locmap{filter:grayscale(0.6)}html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data .locmap div{background:transparent!important}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .locmap{filter:grayscale(0.6)}html.skin-theme-clientpref-os .mw-parser-output .od,html.skin-theme-clientpref-os .mw-parser-output .od .pv>div,html.skin-theme-clientpref-os .mw-parser-output .od .pl>div,html.skin-theme-clientpref-os .mw-parser-output .od .pr>div{background:white!important;color:#000!important}html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data .locmap div{background:transparent!important}}</style><div class="center"><div class="locmap" style="width:250px;float:none;clear:both;margin-left:auto;margin-right:auto"><div style="width:250px;padding:0"><div style="position:relative;width:250px"><span class="notpageimage" typeof="mw:File"><a href="/wiki/File:USA_New_Mexico_location_map.svg" class="mw-file-description" title="Project Y is located in New Mexico"><img alt="Project Y is located in New Mexico" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/10/USA_New_Mexico_location_map.svg/250px-USA_New_Mexico_location_map.svg.png" decoding="async" width="250" height="281" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/10/USA_New_Mexico_location_map.svg/375px-USA_New_Mexico_location_map.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/10/USA_New_Mexico_location_map.svg/500px-USA_New_Mexico_location_map.svg.png 2x" data-file-width="1245" data-file-height="1401" /></a></span><div class="od notheme" style="top:21.612%;left:46.18%;font-size:91%"><div class="id" style="left:-4px;top:-4px"><span class="notpageimage" typeof="mw:File"><span title="Project Y"><img alt="Project Y" src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/7px-Red_pog.svg.png" decoding="async" width="7" height="7" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/11px-Red_pog.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/14px-Red_pog.svg.png 2x" data-file-width="64" data-file-height="64" /></span></span></div></div></div><div style="padding-top:0.2em"></div><span class="switcher-label" style="display:none">Show map of New Mexico</span></div></div></div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238443738"><div class="center"><div class="locmap" style="width:250px;float:none;clear:both;margin-left:auto;margin-right:auto"><div style="width:250px;padding:0"><div style="position:relative;width:250px"><span class="notpageimage" typeof="mw:File"><a href="/wiki/File:Usa_edcp_location_map.svg" class="mw-file-description" title="Project Y is located in the United States"><img alt="Project Y is located in the United States" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Usa_edcp_location_map.svg/250px-Usa_edcp_location_map.svg.png" decoding="async" width="250" height="155" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Usa_edcp_location_map.svg/375px-Usa_edcp_location_map.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/20/Usa_edcp_location_map.svg/500px-Usa_edcp_location_map.svg.png 2x" data-file-width="1181" data-file-height="731" /></a></span><div class="od notheme" style="top:57.579%;left:32.037%;font-size:91%"><div class="id" style="left:-4px;top:-4px"><span class="notpageimage" typeof="mw:File"><span title="Project Y"><img alt="Project Y" src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/7px-Red_pog.svg.png" decoding="async" width="7" height="7" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/11px-Red_pog.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0c/Red_pog.svg/14px-Red_pog.svg.png 2x" data-file-width="64" data-file-height="64" /></span></span></div></div></div><div style="padding-top:0.2em"></div><span class="switcher-label" style="display:none">Show map of the United States</span></div></div></div></div></td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">Location</th><td class="infobox-data" style="border: 0;">Central Ave., <a href="/wiki/Los_Alamos,_New_Mexico" title="Los Alamos, New Mexico">Los Alamos</a>, New Mexico</td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">Coordinates</th><td class="infobox-data" style="border: 0;"><span class="geo-inline"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1156832818"><span class="plainlinks nourlexpansion"><a class="external text" href="https://geohack.toolforge.org/geohack.php?pagename=Project_Y&amp;params=35_52_54_N_106_17_54_W_type:landmark_region:US-NM"><span class="geo-default"><span class="geo-dms" title="Maps, aerial photos, and other data for this location"><span class="latitude">35°52′54″N</span> <span class="longitude">106°17′54″W</span></span></span><span class="geo-multi-punct">&#xfeff; / &#xfeff;</span><span class="geo-nondefault"><span class="geo-dec" title="Maps, aerial photos, and other data for this location">35.88167°N 106.29833°W</span><span style="display:none">&#xfeff; / <span class="geo">35.88167; -106.29833</span></span></span></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">Built</th><td class="infobox-data" style="border: 0;">1943</td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">Architectural&#160;style</th><td class="infobox-data" style="border: 0;">Bungalow/Craftsman, Modern Movement</td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">NRHP&#160;reference&#160;<abbr title="number">No.</abbr></th><td class="infobox-data" style="border: 0;"><a rel="nofollow" class="external text" href="https://npgallery.nps.gov/AssetDetail/NRIS/66000893">66000893</a><sup id="cite_ref-nris_1-0" class="reference"><a href="#cite_note-nris-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup></td></tr><tr><th scope="row" class="infobox-label" style="font-weight:bold; border: 0;">Added to NRHP</th><td class="infobox-data" style="border: 0;">15 October 1966</td></tr><tr style="display:none"><td colspan="2"> </td></tr></tbody></table> <p>The <b>Los Alamos Laboratory</b>, also known as <b>Project Y</b>, was a secret laboratory established by the <a href="/wiki/Manhattan_Project" title="Manhattan Project">Manhattan Project</a> and operated by the <a href="/wiki/University_of_California" title="University of California">University of California</a> during <a href="/wiki/World_War_II" title="World War II">World War II</a>. Its mission was to design and build the <a href="/wiki/History_of_nuclear_weapons" title="History of nuclear weapons">first atomic bombs</a>. <a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a> was its first director, serving from 1943 to December 1945, when he was succeeded by <a href="/wiki/Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a>. In order to enable scientists to freely discuss their work while preserving security, the laboratory was located on the isolated <a href="/wiki/Pajarito_Plateau" title="Pajarito Plateau">Pajarito Plateau</a> in Northern <a href="/wiki/New_Mexico" title="New Mexico">New Mexico</a>. The wartime laboratory occupied buildings that had once been part of the <a href="/wiki/Los_Alamos_Ranch_School" title="Los Alamos Ranch School">Los Alamos Ranch School</a>. </p><p>The development effort initially focused on a <a href="/wiki/Gun-type_fission_weapon" title="Gun-type fission weapon">gun-type fission weapon</a> using <a href="/wiki/Plutonium" title="Plutonium">plutonium</a> called <a href="/wiki/Thin_Man_(nuclear_bomb)" title="Thin Man (nuclear bomb)">Thin Man</a>. In April 1944, the Los Alamos Laboratory determined that the rate of <a href="/wiki/Spontaneous_fission" title="Spontaneous fission">spontaneous fission</a> in plutonium bred in a nuclear reactor was too great due to the presence of <a href="/wiki/Plutonium-240" title="Plutonium-240">plutonium-240</a> and would cause a <a href="/wiki/Fizzle_(nuclear_test)" class="mw-redirect" title="Fizzle (nuclear test)">predetonation</a>, a <a href="/wiki/Nuclear_chain_reaction" title="Nuclear chain reaction">nuclear chain reaction</a> before the <a href="/wiki/Pit_(nuclear_weapon)" title="Pit (nuclear weapon)">core</a> was fully assembled. Oppenheimer then reorganized the laboratory and orchestrated an all-out and ultimately successful effort on an alternative design proposed by <a href="/wiki/John_von_Neumann" title="John von Neumann">John von Neumann</a>, an <a href="/wiki/Implosion-type_nuclear_weapon" class="mw-redirect" title="Implosion-type nuclear weapon">implosion-type nuclear weapon</a>, which was called <a href="/wiki/Fat_Man" title="Fat Man">Fat Man</a>. A variant of the gun-type design known as <a href="/wiki/Little_Boy" title="Little Boy">Little Boy</a> was developed using <a href="/wiki/Uranium-235" title="Uranium-235">uranium-235</a>. </p><p>Chemists at the Los Alamos Laboratory developed methods of purifying uranium and plutonium, the latter a metal that only existed in microscopic quantities when Project Y began. Its metallurgists found that plutonium had unexpected properties, but were nonetheless able to cast it into metal spheres. The laboratory built the Water Boiler, an <a href="/wiki/Aqueous_homogeneous_reactor" title="Aqueous homogeneous reactor">aqueous homogeneous reactor</a> that was the third reactor in the world to become operational. It also researched the Super, a <a href="/wiki/Hydrogen_bomb" class="mw-redirect" title="Hydrogen bomb">hydrogen bomb</a> that would use a fission bomb to ignite a <a href="/wiki/Nuclear_fusion" title="Nuclear fusion">nuclear fusion</a> reaction in <a href="/wiki/Deuterium" title="Deuterium">deuterium</a> and <a href="/wiki/Tritium" title="Tritium">tritium</a>. </p><p>The Fat Man design was tested in the <a href="/wiki/Trinity_nuclear_test" class="mw-redirect" title="Trinity nuclear test">Trinity nuclear test</a> in July 1945. Project Y personnel formed pit crews and assembly teams for the <a href="/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki" title="Atomic bombings of Hiroshima and Nagasaki">atomic bombings of Hiroshima and Nagasaki</a> and participated in the bombing as weaponeers and observers. After the war ended, the laboratory supported the <a href="/wiki/Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a> nuclear tests at <a href="/wiki/Bikini_Atoll" title="Bikini Atoll">Bikini Atoll</a>. A new Z Division was created to control testing, stockpiling and bomb assembly activities, which were concentrated at <a href="/wiki/Sandia_Base" title="Sandia Base">Sandia Base</a>. The Los Alamos Laboratory became <a href="/wiki/Los_Alamos_Scientific_Laboratory" class="mw-redirect" title="Los Alamos Scientific Laboratory">Los Alamos Scientific Laboratory</a> in 1947. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Origins">Origins</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=1" title="Edit section: Origins"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Nuclear_fission_and_atomic_bombs">Nuclear fission and atomic bombs</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=2" title="Edit section: Nuclear fission and atomic bombs"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The discovery of the <a href="/wiki/Neutron" title="Neutron">neutron</a> by <a href="/wiki/James_Chadwick" title="James Chadwick">James Chadwick</a> in 1932,<sup id="cite_ref-FOOTNOTECompton195614_2-0" class="reference"><a href="#cite_note-FOOTNOTECompton195614-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> followed by the <a href="/wiki/Discovery_of_nuclear_fission" title="Discovery of nuclear fission">discovery of nuclear fission</a> by chemists <a href="/wiki/Otto_Hahn" title="Otto Hahn">Otto Hahn</a> and <a href="/wiki/Fritz_Strassmann" title="Fritz Strassmann">Fritz Strassmann</a> in 1938,<sup id="cite_ref-FOOTNOTERhodes1986251–254_3-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986251–254-3"><span class="cite-bracket">&#91;</span>3<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">&#91;</span>4<span class="cite-bracket">&#93;</span></a></sup> and its explanation (and naming) by physicists <a href="/wiki/Lise_Meitner" title="Lise Meitner">Lise Meitner</a> and <a href="/wiki/Otto_Frisch" class="mw-redirect" title="Otto Frisch">Otto Frisch</a> soon after,<sup id="cite_ref-FOOTNOTERhodes1986256–263_5-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986256–263-5"><span class="cite-bracket">&#91;</span>5<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup> opened up the possibility of a controlled <a href="/wiki/Nuclear_chain_reaction" title="Nuclear chain reaction">nuclear chain reaction</a> using <a href="/wiki/Uranium" title="Uranium">uranium</a>. At the time, few scientists in the United States thought that an <a href="/wiki/Atomic_bomb" class="mw-redirect" title="Atomic bomb">atomic bomb</a> was practical,<sup id="cite_ref-FOOTNOTEHewlettAnderson196229_7-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson196229-7"><span class="cite-bracket">&#91;</span>7<span class="cite-bracket">&#93;</span></a></sup> but the possibility that a <a href="/wiki/German_atomic_bomb_project" class="mw-redirect" title="German atomic bomb project">German atomic bomb project</a> would develop atomic weapons concerned refugee scientists from <a href="/wiki/Nazi_Germany" title="Nazi Germany">Nazi Germany</a> and other fascist countries, leading to the drafting of the <a href="/wiki/Einstein%E2%80%93Szilard_letter" title="Einstein–Szilard letter">Einstein–Szilard letter</a> to warn President <a href="/wiki/Franklin_D._Roosevelt" title="Franklin D. Roosevelt">Franklin D. Roosevelt</a>. This prompted preliminary research in the United States, beginning in late 1939.<sup id="cite_ref-FOOTNOTEJones198512_8-0" class="reference"><a href="#cite_note-FOOTNOTEJones198512-8"><span class="cite-bracket">&#91;</span>8<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Kernspaltung.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Kernspaltung.gif/220px-Kernspaltung.gif" decoding="async" width="220" height="154" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Kernspaltung.gif/330px-Kernspaltung.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Kernspaltung.gif/440px-Kernspaltung.gif 2x" data-file-width="848" data-file-height="592" /></a><figcaption>In <a href="/wiki/Nuclear_fission" title="Nuclear fission">nuclear fission</a>, the <a href="/wiki/Atomic_nucleus" title="Atomic nucleus">atomic nucleus</a> of a heavy element splits into two or more light ones when a <a href="/wiki/Neutron" title="Neutron">neutron</a> is captured. If more neutrons are emitted, a <a href="/wiki/Nuclear_chain_reaction" title="Nuclear chain reaction">nuclear chain reaction</a> becomes possible.</figcaption></figure> <p>Progress was slow in the United States, but in Britain, Otto Frisch and <a href="/wiki/Rudolf_Peierls" title="Rudolf Peierls">Rudolf Peierls</a>, two refugee physicists from Germany at the <a href="/wiki/University_of_Birmingham" title="University of Birmingham">University of Birmingham</a>, examined the theoretical issues involved in developing, producing and using atomic bombs. They considered what would happen to a sphere of pure uranium-235, and found that not only could a <a href="/wiki/Chain_reaction" title="Chain reaction">chain reaction</a> occur, but it might require as little as 1 kilogram (2.2&#160;lb) of <a href="/wiki/Uranium-235" title="Uranium-235">uranium-235</a> to unleash the energy of hundreds of tons of <a href="/wiki/TNT" title="TNT">TNT</a>. Their superior, <a href="/wiki/Mark_Oliphant" title="Mark Oliphant">Mark Oliphant</a>, took the <a href="/wiki/Frisch%E2%80%93Peierls_memorandum" title="Frisch–Peierls memorandum">Frisch–Peierls memorandum</a> to Sir <a href="/wiki/Henry_Tizard" title="Henry Tizard">Henry Tizard</a>, the chairman of the <a href="/wiki/Committee_for_the_Scientific_Survey_of_Air_Warfare" class="mw-redirect" title="Committee for the Scientific Survey of Air Warfare">Committee for the Scientific Survey of Air Warfare</a> (CSSAW), who in turn passed it on to <a href="/wiki/George_Paget_Thomson" title="George Paget Thomson">George Paget Thomson</a>, to whom the CSSAW had delegated responsibility for uranium research.<sup id="cite_ref-FOOTNOTEGowing196439–43,_407_9-0" class="reference"><a href="#cite_note-FOOTNOTEGowing196439–43,_407-9"><span class="cite-bracket">&#91;</span>9<span class="cite-bracket">&#93;</span></a></sup> CSSAW created the <a href="/wiki/MAUD_Committee" title="MAUD Committee">MAUD Committee</a> to investigate.<sup id="cite_ref-FOOTNOTEGowing196443–45_10-0" class="reference"><a href="#cite_note-FOOTNOTEGowing196443–45-10"><span class="cite-bracket">&#91;</span>10<span class="cite-bracket">&#93;</span></a></sup> In its final report in July 1941, the MAUD Committee concluded that an atomic bomb was not only feasible, but might be produced as early as 1943.<sup id="cite_ref-FOOTNOTEGowing196478_11-0" class="reference"><a href="#cite_note-FOOTNOTEGowing196478-11"><span class="cite-bracket">&#91;</span>11<span class="cite-bracket">&#93;</span></a></sup> In response, the British government created a nuclear weapons project known as <a href="/wiki/Tube_Alloys" title="Tube Alloys">Tube Alloys</a>.<sup id="cite_ref-FOOTNOTEGowing1964107–109_12-0" class="reference"><a href="#cite_note-FOOTNOTEGowing1964107–109-12"><span class="cite-bracket">&#91;</span>12<span class="cite-bracket">&#93;</span></a></sup> </p><p>There was still little urgency in the United States, which unlike Britain was not yet engaged in <a href="/wiki/World_War_II" title="World War II">World War II</a>, so Oliphant flew there in late August 1941,<sup id="cite_ref-FOOTNOTERhodes1986372_13-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986372-13"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> and spoke to American scientists including his friend <a href="/wiki/Ernest_Lawrence" title="Ernest Lawrence">Ernest Lawrence</a> at the <a href="/wiki/University_of_California,_Berkeley" title="University of California, Berkeley">University of California</a>. He not only managed to convince them that an atomic bomb was feasible, but inspired Lawrence to convert his 37-inch (94&#160;cm) cyclotron into a giant <a href="/wiki/Mass_spectrometer" class="mw-redirect" title="Mass spectrometer">mass spectrometer</a> for <a href="/wiki/Isotope_separation" title="Isotope separation">isotope separation</a>,<sup id="cite_ref-FOOTNOTEHewlettAnderson196243–44_14-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson196243–44-14"><span class="cite-bracket">&#91;</span>14<span class="cite-bracket">&#93;</span></a></sup> a technique Oliphant had pioneered in 1934.<sup id="cite_ref-Electromagnetic_separation_15-0" class="reference"><a href="#cite_note-Electromagnetic_separation-15"><span class="cite-bracket">&#91;</span>15<span class="cite-bracket">&#93;</span></a></sup> In turn, Lawrence brought in his friend and colleague <a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a> to double-check the physics of the MAUD Committee report, which was discussed at a meeting at the <a href="/wiki/General_Electric_Research_Laboratory" title="General Electric Research Laboratory">General Electric Research Laboratory</a> in <a href="/wiki/Schenectady,_New_York" title="Schenectady, New York">Schenectady, New York</a>, on 21 October 1941.<sup id="cite_ref-FOOTNOTEHewlettAnderson196246–47_16-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson196246–47-16"><span class="cite-bracket">&#91;</span>16<span class="cite-bracket">&#93;</span></a></sup> </p><p>In December 1941, the <a href="/wiki/S-1_Section" class="mw-redirect" title="S-1 Section">S-1 Section</a> of the <a href="/wiki/Office_of_Scientific_Research_and_Development" title="Office of Scientific Research and Development">Office of Scientific Research and Development</a> (OSRD) placed <a href="/wiki/Arthur_H._Compton" class="mw-redirect" title="Arthur H. Compton">Arthur H. Compton</a> in charge of overseeing the scientific research for production and design of the bomb.<sup id="cite_ref-FOOTNOTEHewlettAnderson196250–51_17-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson196250–51-17"><span class="cite-bracket">&#91;</span>17<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTECompton195686_18-0" class="reference"><a href="#cite_note-FOOTNOTECompton195686-18"><span class="cite-bracket">&#91;</span>18<span class="cite-bracket">&#93;</span></a></sup> He delegated bomb design and the making of <a href="/wiki/Fast_neutron_calculations" class="mw-redirect" title="Fast neutron calculations">fast neutron calculations</a>—the key to calculations of critical mass and weapon detonation—to <a href="/wiki/Gregory_Breit" title="Gregory Breit">Gregory Breit</a>, who was given the title of "Co-ordinator of Rapid Rupture", and Oppenheimer as an assistant. But Breit disagreed with other scientists working at the <a href="/wiki/Metallurgical_Laboratory" title="Metallurgical Laboratory">Metallurgical Laboratory</a>, particularly <a href="/wiki/Enrico_Fermi" title="Enrico Fermi">Enrico Fermi</a>, over the security arrangements,<sup id="cite_ref-FOOTNOTEMonk2012312–315_19-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012312–315-19"><span class="cite-bracket">&#91;</span>19<span class="cite-bracket">&#93;</span></a></sup> and resigned on 18 May 1942.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962103_20-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962103-20"><span class="cite-bracket">&#91;</span>20<span class="cite-bracket">&#93;</span></a></sup> Compton then appointed Oppenheimer to replace him.<sup id="cite_ref-FOOTNOTECompton1956125–127_21-0" class="reference"><a href="#cite_note-FOOTNOTECompton1956125–127-21"><span class="cite-bracket">&#91;</span>21<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/John_H._Manley" class="mw-redirect" title="John H. Manley">John H. Manley</a>, a physicist at the Metallurgical Laboratory, was assigned to assist Oppenheimer by contacting and coordinating experimental physics groups scattered across the country.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962103_20-1" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962103-20"><span class="cite-bracket">&#91;</span>20<span class="cite-bracket">&#93;</span></a></sup> Oppenheimer and <a href="/wiki/Robert_Serber" title="Robert Serber">Robert Serber</a> of the <a href="/wiki/University_of_Illinois_at_Urbana-Champaign" class="mw-redirect" title="University of Illinois at Urbana-Champaign">University of Illinois</a> examined the problems of neutron diffusion—how neutrons moved in a nuclear chain reaction—and <a href="/wiki/Hydrodynamics" class="mw-redirect" title="Hydrodynamics">hydrodynamics</a>—how the explosion produced by a chain reaction might behave.<sup id="cite_ref-FOOTNOTEMonk2012315–316_22-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012315–316-22"><span class="cite-bracket">&#91;</span>22<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Bomb_design_concepts">Bomb design concepts</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=3" title="Edit section: Bomb design concepts"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Deuterium-tritium_fusion.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Deuterium-tritium_fusion.svg/170px-Deuterium-tritium_fusion.svg.png" decoding="async" width="170" height="204" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Deuterium-tritium_fusion.svg/255px-Deuterium-tritium_fusion.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3b/Deuterium-tritium_fusion.svg/340px-Deuterium-tritium_fusion.svg.png 2x" data-file-width="500" data-file-height="600" /></a><figcaption>In <a href="/wiki/Nuclear_fusion" title="Nuclear fusion">nuclear fusion</a>, the nuclei of light elements are fused to create a heavier element.</figcaption></figure> <p>To review this work and the general theory of fission reactions, Oppenheimer and Fermi convened meetings at the <a href="/wiki/University_of_Chicago" title="University of Chicago">University of Chicago</a> in June and at the University of California in Berkeley, in July with theoretical physicists <a href="/wiki/Hans_Bethe" title="Hans Bethe">Hans Bethe</a>, <a href="/wiki/John_Van_Vleck" class="mw-redirect" title="John Van Vleck">John Van Vleck</a>, <a href="/wiki/Edward_Teller" title="Edward Teller">Edward Teller</a>, <a href="/wiki/Emil_Konopinski" title="Emil Konopinski">Emil Konopinski</a>, Robert Serber, <a href="/wiki/Stan_Frankel" title="Stan Frankel">Stan Frankel</a>, and Eldred C. Nelson, the latter three former students of Oppenheimer, and <a href="/wiki/Experimental_physicist" class="mw-redirect" title="Experimental physicist">experimental physicists</a> <a href="/wiki/Emilio_Segr%C3%A8" title="Emilio Segrè">Emilio Segrè</a>, <a href="/wiki/Felix_Bloch" title="Felix Bloch">Felix Bloch</a>, <a href="/wiki/Franco_Rasetti" title="Franco Rasetti">Franco Rasetti</a>, John Manley, and <a href="/wiki/Edwin_McMillan" title="Edwin McMillan">Edwin McMillan</a>. They tentatively confirmed that a fission bomb was theoretically possible.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199342–44_23-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199342–44-23"><span class="cite-bracket">&#91;</span>23<span class="cite-bracket">&#93;</span></a></sup> </p><p>There were still many unknown factors. The properties of pure uranium-235 were relatively unknown; even more so those of <a href="/wiki/Plutonium" title="Plutonium">plutonium</a>, a <a href="/wiki/Chemical_element" title="Chemical element">chemical element</a> that had only recently been discovered by <a href="/wiki/Glenn_Seaborg" class="mw-redirect" title="Glenn Seaborg">Glenn Seaborg</a> and his team in February 1941, but which was theoretically <a href="/wiki/Fissile" class="mw-redirect" title="Fissile">fissile</a>. The scientists at the Berkeley conference envisioned breeding plutonium in <a href="/wiki/Nuclear_reactor" title="Nuclear reactor">nuclear reactors</a> from <a href="/wiki/Uranium-238" title="Uranium-238">uranium-238</a> atoms that absorbed neutrons from fissioning uranium-235 atoms. At this point no reactor had been built, and only microscopic quantities of plutonium were available that had been produced by <a href="/wiki/Cyclotron" title="Cyclotron">cyclotrons</a>.<sup id="cite_ref-FOOTNOTEHewlettAnderson196233–35_24-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson196233–35-24"><span class="cite-bracket">&#91;</span>24<span class="cite-bracket">&#93;</span></a></sup> </p><p>There were many ways of arranging the fissile material into a critical mass. The simplest was shooting a "cylindrical plug" into a sphere of "active material" with a "<a href="/wiki/Tamper_(nuclear_weapons)" class="mw-redirect" title="Tamper (nuclear weapons)">tamper</a>"—dense material that would focus neutrons inward and keep the reacting mass together to increase its efficiency.<sup id="cite_ref-FOOTNOTESerberRhodes199221_25-0" class="reference"><a href="#cite_note-FOOTNOTESerberRhodes199221-25"><span class="cite-bracket">&#91;</span>25<span class="cite-bracket">&#93;</span></a></sup> They also explored designs involving <a href="/wiki/Spheroid" title="Spheroid">spheroids</a>, a primitive form of "implosion" suggested by <a href="/wiki/Richard_C._Tolman" title="Richard C. Tolman">Richard C. Tolman</a>, and the possibility of <a href="/wiki/Autocatalysis" title="Autocatalysis">autocatalytic methods</a>, which would increase the efficiency of the bomb as it exploded.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199354–56_26-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199354–56-26"><span class="cite-bracket">&#91;</span>26<span class="cite-bracket">&#93;</span></a></sup> </p><p>Considering the idea of the fission bomb theoretically settled—at least until more experimental data was available—the Berkeley conference then turned in a different direction. Edward Teller pushed for discussion of a more powerful bomb: the "Super", usually referred to today as a "<a href="/wiki/Hydrogen_bomb" class="mw-redirect" title="Hydrogen bomb">hydrogen bomb</a>", which would use the explosive force of a detonating fission bomb to ignite a <a href="/wiki/Nuclear_fusion" title="Nuclear fusion">nuclear fusion</a> reaction between <a href="/wiki/Deuterium" title="Deuterium">deuterium</a> and <a href="/wiki/Tritium" title="Tritium">tritium</a>.<sup id="cite_ref-FOOTNOTERhodes1986417_27-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986417-27"><span class="cite-bracket">&#91;</span>27<span class="cite-bracket">&#93;</span></a></sup> Teller proposed scheme after scheme, but Bethe rejected each one. The fusion idea was set aside to concentrate on producing fission bombs.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199344–45_28-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199344–45-28"><span class="cite-bracket">&#91;</span>28<span class="cite-bracket">&#93;</span></a></sup> Teller also raised the speculative possibility that an atomic bomb might "ignite" the atmosphere because of a hypothetical fusion reaction of nitrogen nuclei,<sup id="cite_ref-FOOTNOTEBethe199130_29-0" class="reference"><a href="#cite_note-FOOTNOTEBethe199130-29"><span class="cite-bracket">&#91;</span>29<span class="cite-bracket">&#93;</span></a></sup> but Bethe calculated that this could not happen,<sup id="cite_ref-FOOTNOTERhodes1986419_30-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986419-30"><span class="cite-bracket">&#91;</span>30<span class="cite-bracket">&#93;</span></a></sup> and a report co-authored with Teller showed that "no self-propagating chain of nuclear reactions is likely to be started".<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">&#91;</span>31<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Bomb_laboratory_concept">Bomb laboratory concept</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=4" title="Edit section: Bomb laboratory concept"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Oppenheimer's deft handling of the July conference impressed his colleagues; his insight and ability to handle even the most difficult people came as a surprise even to those who knew him well.<sup id="cite_ref-FOOTNOTEMonk2012321_32-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012321-32"><span class="cite-bracket">&#91;</span>32<span class="cite-bracket">&#93;</span></a></sup> In the wake of the conference, Oppenheimer saw that while they had come to grips with the physics, considerable work was still required on the engineering, chemistry, metallurgy and ordnance aspects of building an atomic bomb. He became convinced that bomb design would require an environment where people could freely discuss problems and thereby reduce wasteful duplication of effort. He reasoned that this could best be reconciled with security by creating a central laboratory in an isolated location.<sup id="cite_ref-FOOTNOTEMonk2012325_33-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012325-33"><span class="cite-bracket">&#91;</span>33<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEJones198582–83_34-0" class="reference"><a href="#cite_note-FOOTNOTEJones198582–83-34"><span class="cite-bracket">&#91;</span>34<span class="cite-bracket">&#93;</span></a></sup> </p><p><a href="/wiki/Brigadier_general_(United_States)" title="Brigadier general (United States)">Brigadier General</a> <a href="/wiki/Leslie_R._Groves_Jr." class="mw-redirect" title="Leslie R. Groves Jr.">Leslie R. Groves Jr.</a> became director of the <a href="/wiki/Manhattan_Project" title="Manhattan Project">Manhattan Project</a> on 23 September 1942.<sup id="cite_ref-FOOTNOTEJones198577_35-0" class="reference"><a href="#cite_note-FOOTNOTEJones198577-35"><span class="cite-bracket">&#91;</span>35<span class="cite-bracket">&#93;</span></a></sup> He visited Berkeley to look at Lawrence's <a href="/wiki/Calutron" title="Calutron">calutrons</a>, and met with Oppenheimer, who gave him a report on bomb design on 8 October.<sup id="cite_ref-FOOTNOTEGroves196260–61_36-0" class="reference"><a href="#cite_note-FOOTNOTEGroves196260–61-36"><span class="cite-bracket">&#91;</span>36<span class="cite-bracket">&#93;</span></a></sup> Groves was interested in Oppenheimer's proposal to establish a separate bomb design laboratory. When they met again in Chicago on October 15, he invited Oppenheimer to discuss the issue. Groves had to catch the <a href="/wiki/20th_Century_Limited" title="20th Century Limited">20th Century Limited</a> train back to New York, so he asked Oppenheimer to accompany him so that they could continue the discussion. Groves, Oppenheimer, <a href="/wiki/Colonel_(United_States)" title="Colonel (United States)">Colonel</a> <a href="/wiki/James_C._Marshall" title="James C. Marshall">James C. Marshall</a>, and <a href="/wiki/Lieutenant_Colonel_(United_States)" class="mw-redirect" title="Lieutenant Colonel (United States)">Lieutenant Colonel</a> <a href="/wiki/Kenneth_Nichols" title="Kenneth Nichols">Kenneth Nichols</a> all squeezed into Nichol's single roomette compartment to discuss how a bomb laboratory could be created and how it would function.<sup id="cite_ref-FOOTNOTEMonk2012325_33-1" class="reference"><a href="#cite_note-FOOTNOTEMonk2012325-33"><span class="cite-bracket">&#91;</span>33<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTENichols198773_37-0" class="reference"><a href="#cite_note-FOOTNOTENichols198773-37"><span class="cite-bracket">&#91;</span>37<span class="cite-bracket">&#93;</span></a></sup> Groves subsequently had Oppenheimer come to <a href="/wiki/Washington,_D.C." title="Washington, D.C.">Washington, D.C.</a>, where the matter was discussed with <a href="/wiki/Vannevar_Bush" title="Vannevar Bush">Vannevar Bush</a>, the director of the OSRD, and <a href="/wiki/James_B._Conant" title="James B. Conant">James B. Conant</a>, the chairman of the <a href="/wiki/National_Defense_Research_Committee" title="National Defense Research Committee">National Defense Research Committee</a> (NDRC). On 19 October, Groves approved the establishment of a bomb laboratory.<sup id="cite_ref-FOOTNOTEJones198582–83_34-1" class="reference"><a href="#cite_note-FOOTNOTEJones198582–83-34"><span class="cite-bracket">&#91;</span>34<span class="cite-bracket">&#93;</span></a></sup> </p><p>While Oppenheimer seemed the logical person to direct the new laboratory, which became known as Project Y, he had little administrative experience; Bush, Conant, Lawrence and <a href="/wiki/Harold_Urey" title="Harold Urey">Harold Urey</a> all expressed reservations about this.<sup id="cite_ref-FOOTNOTEJones198587_38-0" class="reference"><a href="#cite_note-FOOTNOTEJones198587-38"><span class="cite-bracket">&#91;</span>38<span class="cite-bracket">&#93;</span></a></sup> Moreover, unlike his other project leaders—Lawrence at the <a href="/wiki/Berkeley_Radiation_Laboratory" class="mw-redirect" title="Berkeley Radiation Laboratory">Berkeley Radiation Laboratory</a>, Compton at the Metallurgical Project in Chicago, and Urey at the <a href="/wiki/SAM_Laboratories" class="mw-redirect" title="SAM Laboratories">SAM Laboratories</a> in New York—Oppenheimer did not have a <a href="/wiki/Nobel_Prize" title="Nobel Prize">Nobel Prize</a>, raising concerns that he might not have the prestige to deal with distinguished scientists. There were also security concerns;<sup id="cite_ref-FOOTNOTEGroves196261–63_39-0" class="reference"><a href="#cite_note-FOOTNOTEGroves196261–63-39"><span class="cite-bracket">&#91;</span>39<span class="cite-bracket">&#93;</span></a></sup> many of Oppenheimer's closest associates were active members of the <a href="/wiki/Communist_Party_USA" title="Communist Party USA">Communist Party</a>, including his wife <a href="/wiki/Katherine_Oppenheimer" title="Katherine Oppenheimer">Kitty</a>,<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">&#91;</span>40<span class="cite-bracket">&#93;</span></a></sup> girlfriend <a href="/wiki/Jean_Tatlock" title="Jean Tatlock">Jean Tatlock</a>,<sup id="cite_ref-FOOTNOTEMonk2012234–236_41-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012234–236-41"><span class="cite-bracket">&#91;</span>41<span class="cite-bracket">&#93;</span></a></sup> brother <a href="/wiki/Frank_Oppenheimer" title="Frank Oppenheimer">Frank</a>, and Frank's wife Jackie.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">&#91;</span>42<span class="cite-bracket">&#93;</span></a></sup> In the end, Groves personally issued instructions to clear Oppenheimer on 20 July 1943.<sup id="cite_ref-FOOTNOTEGroves196261–63_39-1" class="reference"><a href="#cite_note-FOOTNOTEGroves196261–63-39"><span class="cite-bracket">&#91;</span>39<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Site_selection">Site selection</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=5" title="Edit section: Site selection"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Los_Alamos_map.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Los_Alamos_map.gif/330px-Los_Alamos_map.gif" decoding="async" width="330" height="423" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Los_Alamos_map.gif/495px-Los_Alamos_map.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/65/Los_Alamos_map.gif/660px-Los_Alamos_map.gif 2x" data-file-width="1000" data-file-height="1283" /></a><figcaption>Map of Los Alamos site, New Mexico, 1943–45</figcaption></figure> <p>The idea of locating Project Y at the Metallurgical Laboratory in Chicago, or the <a href="/wiki/Clinton_Engineer_Works" title="Clinton Engineer Works">Clinton Engineer Works</a> in <a href="/wiki/Oak_Ridge,_Tennessee" title="Oak Ridge, Tennessee">Oak Ridge, Tennessee</a>, was considered, but in the end it was decided that a remote location would be best.<sup id="cite_ref-FOOTNOTEJones198583–84_43-0" class="reference"><a href="#cite_note-FOOTNOTEJones198583–84-43"><span class="cite-bracket">&#91;</span>43<span class="cite-bracket">&#93;</span></a></sup> A site in the vicinity of <a href="/wiki/Los_Angeles" title="Los Angeles">Los Angeles</a> was rejected on security grounds, and one near <a href="/wiki/Reno,_Nevada" title="Reno, Nevada">Reno, Nevada</a> as being too inaccessible. On Oppenheimer's recommendation, the search was narrowed to the vicinity of <a href="/wiki/Albuquerque,_New_Mexico" title="Albuquerque, New Mexico">Albuquerque, New Mexico</a>, where Oppenheimer owned a ranch in the <a href="/wiki/Sangre_de_Cristo_Range" title="Sangre de Cristo Range">Sangre de Cristo Range</a>.<sup id="cite_ref-FOOTNOTEGroves196264–65_44-0" class="reference"><a href="#cite_note-FOOTNOTEGroves196264–65-44"><span class="cite-bracket">&#91;</span>44<span class="cite-bracket">&#93;</span></a></sup> The climate was mild, there were air and rail connections to Albuquerque, it was sufficiently distant from the <a href="/wiki/West_Coast_of_the_United_States" title="West Coast of the United States">West Coast of the United States</a> for a Japanese attack not to be an issue, and the population density was low.<sup id="cite_ref-FOOTNOTEJones198583–84_43-1" class="reference"><a href="#cite_note-FOOTNOTEJones198583–84-43"><span class="cite-bracket">&#91;</span>43<span class="cite-bracket">&#93;</span></a></sup> </p><p>In October 1942, Major <a href="/wiki/John_H._Dudley" title="John H. Dudley">John H. Dudley</a> of the Manhattan District (the military component of the Manhattan Project) surveyed sites around <a href="/wiki/Gallup,_New_Mexico" title="Gallup, New Mexico">Gallup</a>, <a href="/wiki/Las_Vegas,_New_Mexico" title="Las Vegas, New Mexico">Las Vegas</a>, La Ventana, <a href="/wiki/Jemez_Springs,_New_Mexico" title="Jemez Springs, New Mexico">Jemez Springs</a>, and <a href="/wiki/Otowi_Historic_District" title="Otowi Historic District">Otowi</a>,<sup id="cite_ref-FOOTNOTETruslow19732_45-0" class="reference"><a href="#cite_note-FOOTNOTETruslow19732-45"><span class="cite-bracket">&#91;</span>45<span class="cite-bracket">&#93;</span></a></sup> and recommended the one near Jemez Springs.<sup id="cite_ref-FOOTNOTEJones198583–84_43-2" class="reference"><a href="#cite_note-FOOTNOTEJones198583–84-43"><span class="cite-bracket">&#91;</span>43<span class="cite-bracket">&#93;</span></a></sup> On 16 November, Oppenheimer, Groves, Dudley and others toured the site. Oppenheimer feared that the high cliffs surrounding the site would make people feel claustrophobic, while the engineers were concerned with the possibility of flooding. The party then moved on to the Otowi site, the vicinity of the <a href="/wiki/Los_Alamos_Ranch_School" title="Los Alamos Ranch School">Los Alamos Ranch School</a>. Oppenheimer was impressed by and expressed a strong preference for the site, citing its natural beauty and views of the <a href="/wiki/Sangre_de_Cristo_Mountains" title="Sangre de Cristo Mountains">Sangre de Cristo Mountains</a>, which, he hoped, would inspire those who would work on the project.<sup id="cite_ref-FOOTNOTEFineRemington1972664–665_46-0" class="reference"><a href="#cite_note-FOOTNOTEFineRemington1972664–665-46"><span class="cite-bracket">&#91;</span>46<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-47" class="reference"><a href="#cite_note-47"><span class="cite-bracket">&#91;</span>47<span class="cite-bracket">&#93;</span></a></sup> The engineers were concerned about the poor access road, and whether the water supply would be adequate, but otherwise felt that it was ideal.<sup id="cite_ref-FOOTNOTEGroves196266–67_48-0" class="reference"><a href="#cite_note-FOOTNOTEGroves196266–67-48"><span class="cite-bracket">&#91;</span>48<span class="cite-bracket">&#93;</span></a></sup> </p><p>The <a href="/wiki/United_States_Under_Secretary_of_War" title="United States Under Secretary of War">United States Under Secretary of War</a>, <a href="/wiki/Robert_P._Patterson" title="Robert P. Patterson">Robert P. Patterson</a>, approved the acquisition of the site on 25 November 1942, authorizing $440,000 for the purchase of the site of 54,000 acres (22,000&#160;ha), all but 8,900 acres (3,600&#160;ha) of which were already owned by the Federal Government.<sup id="cite_ref-FOOTNOTEJones1985328–331_49-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985328–331-49"><span class="cite-bracket">&#91;</span>49<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Secretary_of_Agriculture" class="mw-redirect" title="Secretary of Agriculture">Secretary of Agriculture</a> <a href="/wiki/Claude_R._Wickard" title="Claude R. Wickard">Claude R. Wickard</a> granted use of some 45,100 acres (18,300&#160;ha) of <a href="/wiki/United_States_Forest_Service" title="United States Forest Service">United States Forest Service</a> land to the <a href="/wiki/United_States_Department_of_War" title="United States Department of War">War Department</a> "for so long as the military necessity continues".<sup id="cite_ref-50" class="reference"><a href="#cite_note-50"><span class="cite-bracket">&#91;</span>50<span class="cite-bracket">&#93;</span></a></sup> The need for land for a new road, and later for a right of way for a 25-mile (40&#160;km) power line, eventually brought wartime land purchases to 45,737 acres (18,509.1&#160;ha), but only $414,971 was ultimately spent.<sup id="cite_ref-FOOTNOTEJones1985328–331_49-1" class="reference"><a href="#cite_note-FOOTNOTEJones1985328–331-49"><span class="cite-bracket">&#91;</span>49<span class="cite-bracket">&#93;</span></a></sup> The big ticket items were the school, which cost $350,000, and the Anchor Ranch, which cost $25,000.<sup id="cite_ref-FOOTNOTEManhattan_District1947a3.6_51-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a3.6-51"><span class="cite-bracket">&#91;</span>51<span class="cite-bracket">&#93;</span></a></sup> Both hired lawyers to negotiate deals with the government, but Hispanic homesteaders were paid as little as $7 an acre (equivalent to $123&#32;in 2023).<sup id="cite_ref-52" class="reference"><a href="#cite_note-52"><span class="cite-bracket">&#91;</span>52<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Grazing_permits" class="mw-redirect" title="Grazing permits">Grazing permits</a> were withdrawn, and private land was purchased or condemned under <a href="/wiki/Eminent_domain" title="Eminent domain">eminent domain</a> using the authority of the <a href="/wiki/War_Powers_Act_of_1941" title="War Powers Act of 1941">Second War Powers Act</a>.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS3_53-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS3-53"><span class="cite-bracket">&#91;</span>53<span class="cite-bracket">&#93;</span></a></sup> Petitions of condemnation were worded to cover all mineral, water, timber and other rights, so private individuals would have no reason whatsoever to enter the area.<sup id="cite_ref-FOOTNOTEManhattan_District1947a3.3_54-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a3.3-54"><span class="cite-bracket">&#91;</span>54<span class="cite-bracket">&#93;</span></a></sup> The site acquired an irregular shape due to abutting the <a href="/wiki/Bandelier_National_Monument" title="Bandelier National Monument">Bandelier National Monument</a> and a Native American sacred burial ground.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS3_53-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS3-53"><span class="cite-bracket">&#91;</span>53<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Construction">Construction</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=6" title="Edit section: Construction"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An important consideration in the acquisition of the site was the existence of the Los Alamos Ranch School. This consisted of 54 buildings, of which 27 were houses, dormitories or other quarters providing 46,626 square feet (4,331.7&#160;m<sup>2</sup>) of accommodation. The remaining buildings included a <a href="/wiki/Sawmill" title="Sawmill">sawmill</a>, <a href="/wiki/Ice_house_(building)" title="Ice house (building)">ice house</a>, <a href="/wiki/Barn" title="Barn">barns</a>, carpentry shop, <a href="/wiki/Stable" title="Stable">stables</a> and <a href="/wiki/Garage_(residential)" title="Garage (residential)">garages</a>, all totalling 29,560 square feet (2,746&#160;m<sup>2</sup>). At the nearby Anchor Ranch there were four houses and a barn.<sup id="cite_ref-FOOTNOTEManhattan_District1947a2.7_55-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a2.7-55"><span class="cite-bracket">&#91;</span>55<span class="cite-bracket">&#93;</span></a></sup> Construction work was supervised by the <a href="/wiki/United_States_Army_Corps_of_Engineers#Divisions_and_districts" title="United States Army Corps of Engineers">Albuquerque Engineer District</a> until 15 March 1944, when the Manhattan Engineer District assumed responsibility.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS3_53-2" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS3-53"><span class="cite-bracket">&#91;</span>53<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Willard_C._Kruger_and_Associates" class="mw-redirect" title="Willard C. Kruger and Associates">Willard C. Kruger and Associates</a> of <a href="/wiki/Santa_Fe,_New_Mexico" title="Santa Fe, New Mexico">Santa Fe, New Mexico</a>, was engaged as architect and engineer. <a href="/wiki/Black_%26_Veatch" title="Black &amp; Veatch">Black &amp; Veatch</a> was brought in for the design of utilities in December 1945. The former was paid $743,706.68 and the latter $164,116 by the time the Manhattan Project ended at the end of 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947as4_56-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947as4-56"><span class="cite-bracket">&#91;</span>56<span class="cite-bracket">&#93;</span></a></sup> The Albuquerque District supervised $9.3 million of construction at Los Alamos, and the Manhattan District, another $30.4 million.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS3_53-3" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS3-53"><span class="cite-bracket">&#91;</span>53<span class="cite-bracket">&#93;</span></a></sup> The initial work was contracted to the M. M. Sundt Company of <a href="/wiki/Tucson,_Arizona" title="Tucson, Arizona">Tucson, Arizona</a>, with work commenced in December 1942. Groves initially allocated $300,000 for construction, three times Oppenheimer's estimate, with a planned completion date of 15 March 1943. It soon became clear that the scope of Project Y was far greater than expected, and by the time Sundt finished on 30 November 1943, over $7&#160;million had been spent.<sup id="cite_ref-FOOTNOTEHunner200431–32_57-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200431–32-57"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup> The Zia Company took over responsibility for maintenance in April 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS5–S6_58-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS5–S6-58"><span class="cite-bracket">&#91;</span>58<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Four-family_apartment_units_at_Los_Alamos.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Four-family_apartment_units_at_Los_Alamos.jpg/220px-Four-family_apartment_units_at_Los_Alamos.jpg" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Four-family_apartment_units_at_Los_Alamos.jpg/330px-Four-family_apartment_units_at_Los_Alamos.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Four-family_apartment_units_at_Los_Alamos.jpg/440px-Four-family_apartment_units_at_Los_Alamos.jpg 2x" data-file-width="780" data-file-height="516" /></a><figcaption>Four-family apartment units at Los Alamos</figcaption></figure> <p>Oppenheimer initially estimated that the work could be performed by 50 scientists and 50 technicians. Groves tripled this number to 300.<sup id="cite_ref-FOOTNOTEHunner200431–32_57-1" class="reference"><a href="#cite_note-FOOTNOTEHunner200431–32-57"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup> The actual population, including family members, was about 3,500 by the end of 1943, 5,700 by the end of 1944, 8,200 by the end of 1945, and 10,000 by the close of 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS19_59-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS19-59"><span class="cite-bracket">&#91;</span>59<span class="cite-bracket">&#93;</span></a></sup> Initially, all of the population were workers, as they were the only ones for whom housing was supplied, but as time went on and more housing became available, the number of dependents increased. This trend accelerated with the end of the war and the replacement of military personnel with civilians with families. Due to the highly classified nature of the work, no census of the population of Los Alamos was conducted until April 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.15_60-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.15-60"><span class="cite-bracket">&#91;</span>60<span class="cite-bracket">&#93;</span></a></sup> Birth certificates of babies born in Los Alamos during the war listed their place of birth as PO Box 1663 in Santa Fe. All letters and packages came through that address.<sup id="cite_ref-FOOTNOTEHunner200440–41_61-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200440–41-61"><span class="cite-bracket">&#91;</span>61<span class="cite-bracket">&#93;</span></a></sup> </p><p>The most desirable accommodation were the six existing log and stone cottages that had once housed the headmaster and the Los Alamos Ranch School faculty. They were the only dwellings at Los Alamos that had bathtubs, and became known as "Bathtub Row".<sup id="cite_ref-FOOTNOTEHunner200431–32_57-2" class="reference"><a href="#cite_note-FOOTNOTEHunner200431–32-57"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEMonk2012339_62-0" class="reference"><a href="#cite_note-FOOTNOTEMonk2012339-62"><span class="cite-bracket">&#91;</span>62<span class="cite-bracket">&#93;</span></a></sup> Oppenheimer lived on Bathtub Row; his next-door neighbor was <a href="/wiki/Captain_(United_States_O-6)" title="Captain (United States O-6)">Captain</a> <a href="/wiki/William_Sterling_Parsons" title="William Sterling Parsons">W. S. "Deak" Parsons</a>, the head of the Ordnance and Engineering Division.<sup id="cite_ref-FOOTNOTEHunner2004193_63-0" class="reference"><a href="#cite_note-FOOTNOTEHunner2004193-63"><span class="cite-bracket">&#91;</span>63<span class="cite-bracket">&#93;</span></a></sup> Parsons' house was slightly larger, because Parsons had two children and Oppenheimer, at that point, had only one.<sup id="cite_ref-FOOTNOTEChristman1998118_64-0" class="reference"><a href="#cite_note-FOOTNOTEChristman1998118-64"><span class="cite-bracket">&#91;</span>64<span class="cite-bracket">&#93;</span></a></sup> After Bathtub Row, the next most desirable accommodation was the apartments built by Sundt. A typical two-storey building held four families. Each Sundt apartment had two or three bedrooms, a kitchen with a cranky black coal stove, and a small bathroom. J. E. Morgan and Sons supplied 56 prefabricated dwellings that became known as "Morganville". The Robert E. McKee Company built a part of the town known as "McKeeville".<sup id="cite_ref-FOOTNOTEHunner200431–32_57-3" class="reference"><a href="#cite_note-FOOTNOTEHunner200431–32-57"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup> In June through October 1943, and again in June and July 1944, numbers outstripped the available accommodation and personnel were temporarily lodged in Frijoles Canyon.<sup id="cite_ref-FOOTNOTEJones1985469_65-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985469-65"><span class="cite-bracket">&#91;</span>65<span class="cite-bracket">&#93;</span></a></sup> The houses at Clinton Engineer Works in Oak Ridge, Tennessee and <a href="/wiki/Hanford_Engineer_Works" title="Hanford Engineer Works">Hanford Engineer Works</a> in Washington state were basic but of a higher standard (as specified by <a href="/wiki/Kenneth_Nichols" title="Kenneth Nichols">Nichols</a>) than the houses at Los Alamos (as specified by <a href="/wiki/Leslie_Groves" title="Leslie Groves">Groves</a>), but Nichols said to Los Alamos scientists that housing there was Groves' problem not his.<sup id="cite_ref-FOOTNOTENichols198759,_175_66-0" class="reference"><a href="#cite_note-FOOTNOTENichols198759,_175-66"><span class="cite-bracket">&#91;</span>66<span class="cite-bracket">&#93;</span></a></sup> </p><p>Rents were set based on the income of the occupant.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS9_67-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS9-67"><span class="cite-bracket">&#91;</span>67<span class="cite-bracket">&#93;</span></a></sup> Transient visitors to Los Alamos were accommodated in the <a href="/wiki/Fuller_Lodge" class="mw-redirect" title="Fuller Lodge">Fuller Lodge</a>, the Guest Cottage or the Big House, which had once been part of the Los Alamos Ranch School.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS8_68-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS8-68"><span class="cite-bracket">&#91;</span>68<span class="cite-bracket">&#93;</span></a></sup> A school was established in 1943, catering for both grade school and high school, and 140 children were enrolled; 350 by 1946. Education was free, as was a nursery school for working mothers.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS16_69-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS16-69"><span class="cite-bracket">&#91;</span>69<span class="cite-bracket">&#93;</span></a></sup> With 18 grade-school teachers, 13 high-school teachers, and a superintendent, it enjoyed an excellent teacher:pupil ratio.<sup id="cite_ref-FOOTNOTEManhattan_District1947a6.65–6.66_70-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a6.65–6.66-70"><span class="cite-bracket">&#91;</span>70<span class="cite-bracket">&#93;</span></a></sup> Numerous technical buildings were constructed. Most were of a semi-permanent type, using <a href="/wiki/Gypsum_board" class="mw-redirect" title="Gypsum board">gypsum board</a>. They were heated from a central heating plant. Initially this was Boiler House No. 1, which had two coal-fired <a href="/wiki/Boiler_(power_generation)" title="Boiler (power generation)">boilers</a>. This was replaced by Boiler House No. 2, which had six oil-fired boilers. In addition to the main site at Los Alamos, some 25 outlying sites were developed for experimental work.<sup id="cite_ref-FOOTNOTEManhattan_District1947aS6–S8_71-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS6–S8-71"><span class="cite-bracket">&#91;</span>71<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Los_Alamos_Tech_Area.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Tech_Area.jpg/220px-Los_Alamos_Tech_Area.jpg" decoding="async" width="220" height="135" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Tech_Area.jpg/330px-Los_Alamos_Tech_Area.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Tech_Area.jpg/440px-Los_Alamos_Tech_Area.jpg 2x" data-file-width="635" data-file-height="391" /></a><figcaption>The Technical Area at Los Alamos. There was a perimeter fence around the entire site, but also an inner fence shown here around the Technical Area.</figcaption></figure> <p>The growth of the town outpaced the sewage system,<sup id="cite_ref-FOOTNOTEManhattan_District1947aS6–S8_71-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS6–S8-71"><span class="cite-bracket">&#91;</span>71<span class="cite-bracket">&#93;</span></a></sup> and by late 1945 there were electrical outages. Lights had to be shut off during the day, and between 7 and 10 pm. Water also ran short. During the autumn of 1945, consumption was 585,000 US gallons (2,210,000&#160;L) per day, but the water supply could furnish only 475,000 US gallons (1,800,000&#160;L). On 19 December, pipes that had been laid above ground to save time in 1943 froze, cutting off the supply completely. Residents had to draw water from 15 tanker trucks that carried 300,000 US gallons (1,100,000&#160;L) per day.<sup id="cite_ref-FOOTNOTEHunner200492–94_72-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200492–94-72"><span class="cite-bracket">&#91;</span>72<span class="cite-bracket">&#93;</span></a></sup> Because its name was secret, Los Alamos was referred to as "Site Y"; to residents it was known as "The Hill".<sup id="cite_ref-FOOTNOTEHunner200429_73-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200429-73"><span class="cite-bracket">&#91;</span>73<span class="cite-bracket">&#93;</span></a></sup> Because they lived on Federal land, the state of New Mexico did not allow residents of Los Alamos to vote in elections, although it did require them to pay state income taxes.<sup id="cite_ref-FOOTNOTEJones1985474–475_74-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985474–475-74"><span class="cite-bracket">&#91;</span>74<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEChambers19994–7_75-0" class="reference"><a href="#cite_note-FOOTNOTEChambers19994–7-75"><span class="cite-bracket">&#91;</span>75<span class="cite-bracket">&#93;</span></a></sup> A drawn-out series of legal and legislative battles lay ahead before the residents of Los Alamos became fully-fledged citizens of New Mexico on 10 June 1949.<sup id="cite_ref-FOOTNOTEChambers199941–49_76-0" class="reference"><a href="#cite_note-FOOTNOTEChambers199941–49-76"><span class="cite-bracket">&#91;</span>76<span class="cite-bracket">&#93;</span></a></sup> </p><p>Initially Los Alamos was to have been a military laboratory with Oppenheimer and other researchers commissioned into the Army. Oppenheimer went so far as to order himself a lieutenant colonel's uniform, but two key physicists, <a href="/wiki/Robert_Bacher" title="Robert Bacher">Robert Bacher</a> and <a href="/wiki/Isidor_Rabi" class="mw-redirect" title="Isidor Rabi">Isidor Rabi</a>, balked at the idea. Conant, Groves and Oppenheimer then devised a compromise whereby the laboratory was operated by the University of California.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962230–232_77-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962230–232-77"><span class="cite-bracket">&#91;</span>77<span class="cite-bracket">&#93;</span></a></sup> Financial and procurement activities were the responsibility of the University of California under a 1 January 1943 <a href="/wiki/Letter_of_intent" title="Letter of intent">letter of intent</a> from the OSRD. This was superseded by a formal contract with the Manhattan District on 20 April 1943, which was backdated to 1 January. Financial operations were directed by the resident business officer, J. A. D. Muncy.<sup id="cite_ref-FOOTNOTEHawkins19615_78-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins19615-78"><span class="cite-bracket">&#91;</span>78<span class="cite-bracket">&#93;</span></a></sup> The intent was that it would be militarized when the time came to finally assemble the bomb, but by this time the Los Alamos Laboratory had grown so large that this was considered both impractical and unnecessary,<sup id="cite_ref-FOOTNOTEJones198587_38-1" class="reference"><a href="#cite_note-FOOTNOTEJones198587-38"><span class="cite-bracket">&#91;</span>38<span class="cite-bracket">&#93;</span></a></sup> as the anticipated difficulties regarding civilians working on dangerous tasks had not occurred.<sup id="cite_ref-FOOTNOTEHawkins19615_78-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins19615-78"><span class="cite-bracket">&#91;</span>78<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Organization">Organization</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=7" title="Edit section: Organization"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Military">Military</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=8" title="Edit section: Military"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Colonel John M. Harman was the first post commander at Los Alamos. He joined the Santa Fe office as a lieutenant colonel on 19 January 1943, and was promoted to colonel on 15 February.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.1–7.2-79"><span class="cite-bracket">&#91;</span>79<span class="cite-bracket">&#93;</span></a></sup> Los Alamos officially became a military establishment on 1 April 1943, and he moved to Los Alamos on 19 April.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.1–7.2-79"><span class="cite-bracket">&#91;</span>79<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEJones198586_80-0" class="reference"><a href="#cite_note-FOOTNOTEJones198586-80"><span class="cite-bracket">&#91;</span>80<span class="cite-bracket">&#93;</span></a></sup> He was succeeded by Lieutenant Colonel C. Whitney Ashbridge, a graduate of the Los Alamos Ranch School,<sup id="cite_ref-FOOTNOTEHunner200416_81-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200416-81"><span class="cite-bracket">&#91;</span>81<span class="cite-bracket">&#93;</span></a></sup> in May 1943. In turn, Ashbridge was succeeded by Lieutenant Colonel Gerald R. Tyler in October 1944,<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-2" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.1–7.2-79"><span class="cite-bracket">&#91;</span>79<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHunner200450_82-0" class="reference"><a href="#cite_note-FOOTNOTEHunner200450-82"><span class="cite-bracket">&#91;</span>82<span class="cite-bracket">&#93;</span></a></sup> Colonel Lyle E. Seaman in November 1945, and Colonel Herb C. Gee in September 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-3" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.1–7.2-79"><span class="cite-bracket">&#91;</span>79<span class="cite-bracket">&#93;</span></a></sup> The post commander was answerable directly to Groves, and was responsible for the township, government property and the military personnel.<sup id="cite_ref-FOOTNOTEGroves1962153–154_83-0" class="reference"><a href="#cite_note-FOOTNOTEGroves1962153–154-83"><span class="cite-bracket">&#91;</span>83<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Los_Alamos_Main_Gate_(2).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Main_Gate_%282%29.jpg/220px-Los_Alamos_Main_Gate_%282%29.jpg" decoding="async" width="220" height="167" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Main_Gate_%282%29.jpg/330px-Los_Alamos_Main_Gate_%282%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Los_Alamos_Main_Gate_%282%29.jpg/440px-Los_Alamos_Main_Gate_%282%29.jpg 2x" data-file-width="540" data-file-height="410" /></a><figcaption>The main gate at Los Alamos</figcaption></figure> <p>Four military units were assigned to the post. The MP Detachment, 4817th Service Command Unit, arrived from <a href="/wiki/Fort_Riley,_Kansas" class="mw-redirect" title="Fort Riley, Kansas">Fort Riley, Kansas</a>, in April 1943. Its initial strength was 7 officers and 196 enlisted men; by December 1946 it had 9 officers and 486 men, and was manning 44 guard posts 24 hours a day.<sup id="cite_ref-FOOTNOTEManhattan_District1947a6.33–6.34_84-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a6.33–6.34-84"><span class="cite-bracket">&#91;</span>84<span class="cite-bracket">&#93;</span></a></sup> The Provisional Engineer Detachment (PED), 4817th Service Command Unit, was activated at <a href="/wiki/Camp_Claiborne,_Louisiana" class="mw-redirect" title="Camp Claiborne, Louisiana">Camp Claiborne, Louisiana</a>, on 10 April 1943. These men performed jobs around the post such as working in the boiler plant, the motor pool and the mess halls. They also maintained the buildings and roads. It reached a peak strength of 465 men, and was disbanded on 1 July 1946.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.2–7.5-85"><span class="cite-bracket">&#91;</span>85<span class="cite-bracket">&#93;</span></a></sup> </p><p>The 1st Provisional <a href="/wiki/Women%27s_Army_Corps" title="Women&#39;s Army Corps">Women's Army Auxiliary Corps</a> (WAAC) Detachment was activated at <a href="/wiki/Fort_Sill,_Oklahoma" class="mw-redirect" title="Fort Sill, Oklahoma">Fort Sill, Oklahoma</a>, on 17 April 1943. Its initial strength was just one officer and seven auxiliaries. The WAAC became the <a href="/wiki/Women%27s_Army_Corps" title="Women&#39;s Army Corps">Women's Army Corps</a> (WAC) on 24 August 1943, and the detachment became part of the 4817th Service Command Unit, with a strength of two officers and 43 enlisted women. They were sworn into the United States Army by Ashbridge. It reached a peak strength of about 260 women in August 1945. The WACs did a wider variety of jobs than the PED; some were cooks, drivers and telephone operators, while others served as librarians, clerks and hospital technicians. Some performed highly specialized scientific research inside the Technical Area.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.2–7.5-85"><span class="cite-bracket">&#91;</span>85<span class="cite-bracket">&#93;</span></a></sup> </p><p>The <a href="/wiki/Special_Engineer_Detachment" title="Special Engineer Detachment">Special Engineer Detachment</a> (SED) was activated in October 1943 as part of the 9812th Technical Service Unit. It was made up of men with technical skills or advanced education, and was mostly drawn from the defunct <a href="/wiki/Army_Specialized_Training_Program" title="Army Specialized Training Program">Army Specialized Training Program</a>.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-2" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.2–7.5-85"><span class="cite-bracket">&#91;</span>85<span class="cite-bracket">&#93;</span></a></sup> War Department policy forbade giving deferments from <a href="/wiki/The_draft" class="mw-redirect" title="The draft">the draft</a> to men under 22, so they were assigned to the SED.<sup id="cite_ref-FOOTNOTEHawkins196143_86-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196143-86"><span class="cite-bracket">&#91;</span>86<span class="cite-bracket">&#93;</span></a></sup> It reached a peak strength of 1,823 men in August 1945. SED personnel worked in all areas of the Los Alamos Laboratory.<sup id="cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-3" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a7.2–7.5-85"><span class="cite-bracket">&#91;</span>85<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Civilian">Civilian</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=9" title="Edit section: Civilian"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Passage_between_buildings_A_and_B,_Tech_Area,_Los_Alamos.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg/220px-Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg" decoding="async" width="220" height="122" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg/330px-Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg/440px-Passage_between_buildings_A_and_B%2C_Tech_Area%2C_Los_Alamos.jpg 2x" data-file-width="600" data-file-height="333" /></a><figcaption>Passage between buildings A and B in the Technical Area</figcaption></figure> <p>As director of the Los Alamos Laboratory, Oppenheimer was no longer answerable to Compton, but reported directly to Groves.<sup id="cite_ref-FOOTNOTEJones198586_80-1" class="reference"><a href="#cite_note-FOOTNOTEJones198586-80"><span class="cite-bracket">&#91;</span>80<span class="cite-bracket">&#93;</span></a></sup> He was responsible for the technical and scientific aspects of Project Y.<sup id="cite_ref-FOOTNOTEGroves1962153–154_83-1" class="reference"><a href="#cite_note-FOOTNOTEGroves1962153–154-83"><span class="cite-bracket">&#91;</span>83<span class="cite-bracket">&#93;</span></a></sup> He assembled the nucleus of his staff from the groups that had been working for him on neutron calculations.<sup id="cite_ref-FOOTNOTEHawkins19615–6_87-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins19615–6-87"><span class="cite-bracket">&#91;</span>87<span class="cite-bracket">&#93;</span></a></sup> These included his secretary, <a href="/wiki/Priscilla_Greene" class="mw-redirect" title="Priscilla Greene">Priscilla Greene</a>,<sup id="cite_ref-FOOTNOTEConant200523_88-0" class="reference"><a href="#cite_note-FOOTNOTEConant200523-88"><span class="cite-bracket">&#91;</span>88<span class="cite-bracket">&#93;</span></a></sup> Serber and McMillan from his own group, and Emilio Segrè and <a href="/wiki/Joseph_W._Kennedy" title="Joseph W. Kennedy">Joseph W. Kennedy</a>'s groups from the University of California, <a href="/wiki/John_Harry_Williams" title="John Harry Williams">J. H. Williams</a>' group from the <a href="/wiki/University_of_Minnesota" title="University of Minnesota">University of Minnesota</a>, <a href="/wiki/Joe_McKibben" class="mw-redirect" title="Joe McKibben">Joe McKibben</a>'s group from the <a href="/wiki/University_of_Wisconsin" class="mw-redirect" title="University of Wisconsin">University of Wisconsin</a>, Felix Bloch's group from <a href="/wiki/Stanford_University" title="Stanford University">Stanford University</a> and <a href="/wiki/Marshall_Holloway" title="Marshall Holloway">Marshall Holloway</a>'s from <a href="/wiki/Purdue_University" title="Purdue University">Purdue University</a>. He also secured the services of Hans Bethe and Robert Bacher from the <a href="/wiki/Radiation_Laboratory" class="mw-redirect" title="Radiation Laboratory">Radiation Laboratory</a> at <a href="/wiki/MIT" class="mw-redirect" title="MIT">MIT</a>, <a href="/wiki/Edward_Teller" title="Edward Teller">Edward Teller</a>, <a href="/wiki/Robert_F._Christy" title="Robert F. Christy">Robert F. Christy</a>, <a href="/wiki/Darol_K._Froman" class="mw-redirect" title="Darol K. Froman">Darol K. Froman</a>, <a href="/wiki/Alvin_C._Graves" title="Alvin C. Graves">Alvin C. Graves</a> and John H. Manley and his group from the Manhattan Project's Metallurgical Laboratory, and <a href="/wiki/Robert_R._Wilson" title="Robert R. Wilson">Robert R. Wilson</a> and his group, which included <a href="/wiki/Richard_Feynman" title="Richard Feynman">Richard Feynman</a>, that had been performing Manhattan Project research at <a href="/wiki/Princeton_University" title="Princeton University">Princeton University</a>. They brought with them a great deal of valuable scientific equipment. Wilson's group dismantled the cyclotron at <a href="/wiki/Harvard_University" title="Harvard University">Harvard University</a> and had it shipped to Los Alamos; McKibben's brought two <a href="/wiki/Van_de_Graaff_generator" title="Van de Graaff generator">Van de Graaff generators</a> from Wisconsin; and Manley's brought the <a href="/wiki/Cockcroft%E2%80%93Walton_accelerator" class="mw-redirect" title="Cockcroft–Walton accelerator">Cockcroft–Walton accelerator</a> from the <a href="/wiki/University_of_Illinois" class="mw-redirect" title="University of Illinois">University of Illinois</a>.<sup id="cite_ref-FOOTNOTEHawkins19615–6_87-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins19615–6-87"><span class="cite-bracket">&#91;</span>87<span class="cite-bracket">&#93;</span></a></sup> </p><p>Communications with the outside world went through a single Forest Service line until April 1943,<sup id="cite_ref-FOOTNOTEGroves1962153_89-0" class="reference"><a href="#cite_note-FOOTNOTEGroves1962153-89"><span class="cite-bracket">&#91;</span>89<span class="cite-bracket">&#93;</span></a></sup> when it was replaced by five Army telephone lines. This was increased to eight in March 1945.<sup id="cite_ref-FOOTNOTEManhattan_District1947a5.23–5.24_90-0" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a5.23–5.24-90"><span class="cite-bracket">&#91;</span>90<span class="cite-bracket">&#93;</span></a></sup> There were also three <a href="/wiki/Teletypewriter" class="mw-redirect" title="Teletypewriter">teletypewriters</a> with encoding machines. The first was installed in March 1943, and two more were added in May 1943. One was removed in November 1945.<sup id="cite_ref-FOOTNOTEManhattan_District1947a5.23–5.24_90-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947a5.23–5.24-90"><span class="cite-bracket">&#91;</span>90<span class="cite-bracket">&#93;</span></a></sup> There were telephones in the offices, but none in private residences, as the Army regarded this as a security hazard. There were some public phones in the township for emergencies. Since there was no way to prevent the lines being tapped, <a href="/wiki/Classified_information" title="Classified information">classified information</a> could not be discussed over the phone lines. Initially the phone lines were operable only during business hours until enough WACs arrived to staff the switchboard around the clock.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993109_91-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993109-91"><span class="cite-bracket">&#91;</span>91<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:HD.4G.026_(10537567494).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/HD.4G.026_%2810537567494%29.jpg/220px-HD.4G.026_%2810537567494%29.jpg" decoding="async" width="220" height="171" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/HD.4G.026_%2810537567494%29.jpg/330px-HD.4G.026_%2810537567494%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/58/HD.4G.026_%2810537567494%29.jpg/440px-HD.4G.026_%2810537567494%29.jpg 2x" data-file-width="2646" data-file-height="2060" /></a><figcaption><a href="/wiki/Isidor_Isaac_Rabi" title="Isidor Isaac Rabi">Isidor Isaac Rabi</a>, <a href="/wiki/Dorothy_McKibbin" title="Dorothy McKibbin">Dorothy McKibbin</a>, <a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a> and <a href="/wiki/Victor_Weisskopf" title="Victor Weisskopf">Victor Weisskopf</a> at Oppenheimer's home in Los Alamos in 1944</figcaption></figure> <p>Women at Los Alamos were encouraged to work, due to the shortage of labor and security concerns over bringing in local workers. About 60 wives of scientists were at work in Technical Area by September 1943. About 200 of the 670 workers in the laboratory, hospital and school were women in October 1944. Most worked in administration, but many women such as <a href="/wiki/Lilli_Hornig" title="Lilli Hornig">Lilli Hornig</a>,<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100_92-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100-92"><span class="cite-bracket">&#91;</span>92<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Jane_Hamilton_Hall" title="Jane Hamilton Hall">Jane Hamilton Hall</a>,<sup id="cite_ref-FOOTNOTEHowesHerzenberg199943–45_93-0" class="reference"><a href="#cite_note-FOOTNOTEHowesHerzenberg199943–45-93"><span class="cite-bracket">&#91;</span>93<span class="cite-bracket">&#93;</span></a></sup> and Peggy Titterton worked as scientists and technicians.<sup id="cite_ref-94" class="reference"><a href="#cite_note-94"><span class="cite-bracket">&#91;</span>94<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Charlotte_Serber" title="Charlotte Serber">Charlotte Serber</a> headed the A-5 (Library) Group.<sup id="cite_ref-FOOTNOTEHawkins1961180_95-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961180-95"><span class="cite-bracket">&#91;</span>95<span class="cite-bracket">&#93;</span></a></sup> A large group of women worked on numerical calculations in the T-5 (Computations) Group.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100_92-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100-92"><span class="cite-bracket">&#91;</span>92<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Dorothy_McKibbin" title="Dorothy McKibbin">Dorothy McKibbin</a> ran the Santa Fe office, which opened at 109 East Palace Avenue on 27 March 1943.<sup id="cite_ref-FOOTNOTESteeper20031–3_96-0" class="reference"><a href="#cite_note-FOOTNOTESteeper20031–3-96"><span class="cite-bracket">&#91;</span>96<span class="cite-bracket">&#93;</span></a></sup> New staff members at the secret Los Alamos site were not given in advance any directions to the site or security credentials. They were told to report to the Santa Fe office, where McKibbin provided them with such things and thereby became the gatekeeper of Los Alamos.<sup id="cite_ref-FOOTNOTEConant200584–85_97-0" class="reference"><a href="#cite_note-FOOTNOTEConant200584–85-97"><span class="cite-bracket">&#91;</span>97<span class="cite-bracket">&#93;</span></a></sup> </p><p>The Los Alamos Laboratory had a governing board, the members of which were Oppenheimer, Bacher, Bethe, Kennedy, D. L. Hughes (Personnel Director), D. P. Mitchell (Procurement Director) and Deak Parsons. McMillan, <a href="/wiki/George_Kistiakowsky" title="George Kistiakowsky">George Kistiakowsky</a> and <a href="/wiki/Kenneth_Bainbridge" title="Kenneth Bainbridge">Kenneth Bainbridge</a> were later added.<sup id="cite_ref-FOOTNOTEHawkins196132,_36_98-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196132,_36-98"><span class="cite-bracket">&#91;</span>98<span class="cite-bracket">&#93;</span></a></sup> The laboratory was organized into five divisions: Administration (A), Theoretical (T) under Bethe, Experimental Physics (P) under Bacher, Chemistry and Metallurgy (CM) under Kennedy, and Ordnance and Engineering (E) under Parsons.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199392_99-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199392-99"><span class="cite-bracket">&#91;</span>99<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins196184,_101,_124,_148_100-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196184,_101,_124,_148-100"><span class="cite-bracket">&#91;</span>100<span class="cite-bracket">&#93;</span></a></sup> All the divisions expanded during 1943 and 1944, but T Division, despite trebling in size, remained the smallest, while E Division grew to be the largest. Security clearance was a problem. Scientists (including, at first, Oppenheimer) had to be given access to the Technical Area without proper clearance. In the interest of efficiency, Groves approved an abbreviated process by which Oppenheimer vouched for senior scientists, and three other employees were sufficient to vouch for a junior scientist or technician.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199393–94_101-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199393–94-101"><span class="cite-bracket">&#91;</span>101<span class="cite-bracket">&#93;</span></a></sup> </p><p>The Los Alamos Laboratory was reinforced by a <a href="/wiki/British_contribution_to_the_Manhattan_Project#Los_Alamos_Laboratory" title="British contribution to the Manhattan Project">British Mission</a> under James Chadwick. The first to arrive were Otto Frisch and <a href="/wiki/Ernest_Titterton" title="Ernest Titterton">Ernest Titterton</a>; later arrivals included <a href="/wiki/Niels_Bohr" title="Niels Bohr">Niels Bohr</a> and his son <a href="/wiki/Aage_Bohr" title="Aage Bohr">Aage Bohr</a>, and Sir <a href="/wiki/G._I._Taylor" title="G. I. Taylor">Geoffrey Taylor</a>, an expert on hydrodynamics who made a major contribution to the understanding of the <a href="/wiki/Rayleigh%E2%80%93Taylor_instability" title="Rayleigh–Taylor instability">Rayleigh–Taylor instability</a>.<sup id="cite_ref-FOOTNOTEHawkins196127–30_102-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196127–30-102"><span class="cite-bracket">&#91;</span>102<span class="cite-bracket">&#93;</span></a></sup> This <a href="/wiki/Instability" title="Instability">instability</a> at the <a href="/wiki/Interface_(chemistry)" class="mw-redirect" title="Interface (chemistry)">interface</a> between two <a href="/wiki/Fluid" title="Fluid">fluids</a> of different <a href="/wiki/Density" title="Density">densities</a> occurs when the lighter fluid is pushing the heavier,<sup id="cite_ref-103" class="reference"><a href="#cite_note-103"><span class="cite-bracket">&#91;</span>103<span class="cite-bracket">&#93;</span></a></sup> and was vital to the interpretation of experiments with explosives, predicting the effects of an explosion, the design of the <a href="/wiki/Neutron_initiator" class="mw-redirect" title="Neutron initiator">neutron initiators</a>, and the design of the atomic bomb itself. Chadwick remained only for a few months; he was succeeded as head of the British Mission by Rudolf Peierls. The original idea, favored by Groves, was that the British scientists would work as a group under Chadwick, who would farm out work to them. This was soon discarded in favor of having the British Mission fully integrated into the laboratory. They worked in most of its divisions, only being excluded from plutonium chemistry and metallurgy.<sup id="cite_ref-FOOTNOTESzasz199218–19_104-0" class="reference"><a href="#cite_note-FOOTNOTESzasz199218–19-104"><span class="cite-bracket">&#91;</span>104<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins196127–30_102-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins196127–30-102"><span class="cite-bracket">&#91;</span>102<span class="cite-bracket">&#93;</span></a></sup> With the passage of the <a href="/wiki/Atomic_Energy_Act_of_1946" title="Atomic Energy Act of 1946">Atomic Energy Act of 1946</a>, known as the McMahon Act, all British government employees had to leave. All had left by the end of 1946, except for Titterton, who was granted a special dispensation, and remained until 12 April 1947. The British Mission ended when he departed.<sup id="cite_ref-FOOTNOTESzasz199246–49_105-0" class="reference"><a href="#cite_note-FOOTNOTESzasz199246–49-105"><span class="cite-bracket">&#91;</span>105<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTETruslowSmith19613_106-0" class="reference"><a href="#cite_note-FOOTNOTETruslowSmith19613-106"><span class="cite-bracket">&#91;</span>106<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Gun-type_weapon_design">Gun-type weapon design</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=10" title="Edit section: Gun-type weapon design"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Research">Research</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=11" title="Edit section: Research"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:492px;max-width:492px"><div class="trow"><div class="theader">Los Alamos Technical Area</div></div><div class="trow"><div class="tsingle" style="width:200px;max-width:200px"><div class="thumbimage" style="height:143px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Los_Alamos_Tech_Area_annotated.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Los_Alamos_Tech_Area_annotated.jpg/198px-Los_Alamos_Tech_Area_annotated.jpg" decoding="async" width="198" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Los_Alamos_Tech_Area_annotated.jpg/297px-Los_Alamos_Tech_Area_annotated.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Los_Alamos_Tech_Area_annotated.jpg/396px-Los_Alamos_Tech_Area_annotated.jpg 2x" data-file-width="600" data-file-height="435" /></a></span></div><div class="thumbcaption text-align-center">Photograph of the Tech Area, with the buildings marked. They seem to be randomly scattered. Ashley Pond and the Fuller Lodge are in the background.</div></div><div class="tsingle" style="width:288px;max-width:288px"><div class="thumbimage" style="height:143px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Los_Alamos_Tech_Area_Map.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Los_Alamos_Tech_Area_Map.jpg/286px-Los_Alamos_Tech_Area_Map.jpg" decoding="async" width="286" height="144" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Los_Alamos_Tech_Area_Map.jpg/429px-Los_Alamos_Tech_Area_Map.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/31/Los_Alamos_Tech_Area_Map.jpg/572px-Los_Alamos_Tech_Area_Map.jpg 2x" data-file-width="600" data-file-height="302" /></a></span></div><div class="thumbcaption text-align-center">Map of the Tech Area</div></div></div></div></div> <p>In 1943, development efforts were directed to a <a href="/wiki/Gun-type_fission_weapon" title="Gun-type fission weapon">gun-type fission weapon</a> using plutonium called <a href="/wiki/Thin_Man_(nuclear_bomb)" title="Thin Man (nuclear bomb)">Thin Man</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993111–114_107-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993111–114-107"><span class="cite-bracket">&#91;</span>107<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins196174–75_108-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196174–75-108"><span class="cite-bracket">&#91;</span>108<span class="cite-bracket">&#93;</span></a></sup> The names for all three atomic bomb designs—<a href="/wiki/Fat_Man" title="Fat Man">Fat Man</a>, Thin Man, and <a href="/wiki/Little_Boy" title="Little Boy">Little Boy</a>—were chosen by Serber based on their shapes. Thin Man was a long device, and its name came from the <a href="/wiki/Dashiell_Hammett" title="Dashiell Hammett">Dashiell Hammett</a> <a href="/wiki/The_Thin_Man" title="The Thin Man">detective novel</a> and <a href="/wiki/The_Thin_Man_(film)" title="The Thin Man (film)">series of movies</a> of the same name. The Fat Man was round and fat, and was named after <a href="/wiki/Sydney_Greenstreet" title="Sydney Greenstreet">Sydney Greenstreet</a>'s "Kasper Gutman" character in <i><a href="/wiki/The_Maltese_Falcon_(1941_film)" title="The Maltese Falcon (1941 film)">The Maltese Falcon</a></i>. Little Boy came last, and was named after <a href="/wiki/Elisha_Cook,_Jr." class="mw-redirect" title="Elisha Cook, Jr.">Elisha Cook, Jr.</a>'s character in the same film, as referred to by <a href="/wiki/Humphrey_Bogart" title="Humphrey Bogart">Humphrey Bogart</a>.<sup id="cite_ref-FOOTNOTESerberCrease1998104_109-0" class="reference"><a href="#cite_note-FOOTNOTESerberCrease1998104-109"><span class="cite-bracket">&#91;</span>109<span class="cite-bracket">&#93;</span></a></sup> </p><p>A series of conferences in April and May 1943 laid out the laboratory's plan for the rest of the year. Oppenheimer estimated the critical mass of a uranium-235 gadget with a formula based on <a href="/wiki/Diffusion" title="Diffusion">diffusion</a> theory derived at Berkeley by Stan Frankel and E. C. Nelson. This gave a value for a uranium-235 gadget with a perfect tamper of 25&#160;kg; but this was only an approximation. It was based on simplifying assumptions, notably that all neutrons had the same speed, that all collisions were <a href="/wiki/Elastic_collision" title="Elastic collision">elastic</a>, that they were scattered <a href="/wiki/Isotropy" title="Isotropy">isotropically</a>, and that the <a href="/wiki/Mean_free_path" title="Mean free path">mean free path</a> of neutrons in the core and tamper were the same. Bethe's T Division, particularly Serber's T-2 (Diffusion Theory) Group and Feynman's T-4 (Diffusion Problems) Groups, would spend the next few months working on improved models.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78_110-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78-110"><span class="cite-bracket">&#91;</span>110<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins196185–88_111-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196185–88-111"><span class="cite-bracket">&#91;</span>111<span class="cite-bracket">&#93;</span></a></sup> Bethe and Feynman also developed a formula for the efficiency of the reaction.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184_112-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184-112"><span class="cite-bracket">&#91;</span>112<span class="cite-bracket">&#93;</span></a></sup> </p><p>No formula could be more accurate than the values put into it; the values for the cross sections were dubious, and had not yet been determined for plutonium. Measurement of these values would be a priority, but the laboratory possessed just 1 gram of uranium-235, and only a few micrograms of plutonium.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78_110-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78-110"><span class="cite-bracket">&#91;</span>110<span class="cite-bracket">&#93;</span></a></sup> This task fell to Bacher's P Division. Williams P-2 (Electrostatic Generator) Group carried out the first experiment in July 1943, when it used the larger of the two Van de Graaff generators to measure the ratio of the neutron per fission in plutonium against that of uranium-235.<sup id="cite_ref-FOOTNOTEHawkins1961103–104_113-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961103–104-113"><span class="cite-bracket">&#91;</span>113<span class="cite-bracket">&#93;</span></a></sup> This involved some negotiation with the Metallurgical Laboratory to obtain 165 μg of plutonium, which was received at Los Alamos on 10 July 1943. Bacher was able to report that the number of neutrons per fission of <a href="/wiki/Plutonium-239" title="Plutonium-239">plutonium-239</a> was 2.64 ± 0.2, about 1.2 times as much as uranium-235.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199378–80_114-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199378–80-114"><span class="cite-bracket">&#91;</span>114<span class="cite-bracket">&#93;</span></a></sup> Titterton and <a href="/wiki/Boyce_McDaniel" title="Boyce McDaniel">Boyce McDaniel</a> of Wilson's P-1 (Cyclotron) Group attempted to measure the time it took for <a href="/wiki/Prompt_neutron" title="Prompt neutron">prompt neutrons</a> to be emitted from a uranium-235 nucleus when it fissions.<sup id="cite_ref-115" class="reference"><a href="#cite_note-115"><span class="cite-bracket">&#91;</span>115<span class="cite-bracket">&#93;</span></a></sup> They calculated that most were emitted in less than 1 <a href="/wiki/Nanosecond" title="Nanosecond">nanosecond</a>. Subsequent experiments demonstrated that fission took less than a nanosecond too. Confirmation of the theorists' contention that the number of neutrons emitted per fission was the same for both <a href="/wiki/Neutron_temperature" title="Neutron temperature">fast and slow neutrons</a> took longer, and was not completed until the autumn of 1944.<sup id="cite_ref-FOOTNOTEHawkins1961103–104_113-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961103–104-113"><span class="cite-bracket">&#91;</span>113<span class="cite-bracket">&#93;</span></a></sup> </p><p><a href="/wiki/John_von_Neumann" title="John von Neumann">John von Neumann</a> visited the Los Alamos Laboratory in September 1943 and participated in discussions of the damage that an atomic bomb would do. He explained that while the damage done by a small explosion was proportional to the <a href="/wiki/Impulse_(physics)" title="Impulse (physics)">impulse</a> (the average pressure of the explosion times its duration), the damage from large explosions such as an atomic bomb would be determined by the peak pressure, which depends on the <a href="/wiki/Cube_root" title="Cube root">cube root</a> of its energy. Bethe then calculated that a 10 kilotonnes of TNT (42&#160;TJ) explosion would result in an overpressure of 0.1 standard atmospheres (10&#160;kPa) at 3.5 kilometers (2.2&#160;mi), and therefore result in severe damage within that radius. Von Neumann also suggested that, because pressure increases when shock waves bounce off solid objects, the damage could be increased if the bomb was detonated at an altitude comparable to the damage radius, approximately 1 to 2 kilometers (3,300 to 6,600&#160;ft).<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184_112-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184-112"><span class="cite-bracket">&#91;</span>112<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins196198–99_116-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196198–99-116"><span class="cite-bracket">&#91;</span>116<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Development">Development</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=12" title="Edit section: Development"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Parsons was appointed the head of Ordnance and Engineering Division in June 1943 on the recommendation of Bush and Conant.<sup id="cite_ref-FOOTNOTEHawkins1961124–125_117-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961124–125-117"><span class="cite-bracket">&#91;</span>117<span class="cite-bracket">&#93;</span></a></sup> To staff the division, Tolman, who acted as a coordinator of the gun development effort, brought in John Streib, <a href="/wiki/Charles_Critchfield" title="Charles Critchfield">Charles Critchfield</a> and <a href="/wiki/Seth_Neddermeyer" title="Seth Neddermeyer">Seth Neddermeyer</a> from the <a href="/wiki/National_Bureau_of_Standards" class="mw-redirect" title="National Bureau of Standards">National Bureau of Standards</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199382–85_118-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199382–85-118"><span class="cite-bracket">&#91;</span>118<span class="cite-bracket">&#93;</span></a></sup> The division was initially organized into five groups, with original group leaders being McMillan of the E-1 (Proving Ground) Group, Kenneth Bainbridge of the E-2 (Instrumentation) Group, <a href="/wiki/Robert_Brode" title="Robert Brode">Robert Brode</a> of the E-3 (Fuse Development) Group, Critchfield of the E-4 (Projectile, Target, and Source) Group and Neddermeyer of the E-5 (Implosion) Group. Two more groups were added in the autumn of 1943, the E-7 (Delivery) Group under <a href="/wiki/Norman_Ramsey" class="mw-redirect" title="Norman Ramsey">Norman Ramsey</a> and the E-8 (Interior Ballistics) Group under <a href="/wiki/Joseph_O._Hirschfelder" title="Joseph O. Hirschfelder">Joseph O. Hirschfelder</a>.<sup id="cite_ref-FOOTNOTEHawkins1961124–125_117-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961124–125-117"><span class="cite-bracket">&#91;</span>117<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Thin_Man_plutonium_gun_bomb_casings.jpg" class="mw-file-description"><img alt="Long, tube-like casings. In the background are several ovoid casings and a tow truck." src="//upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Thin_Man_plutonium_gun_bomb_casings.jpg/220px-Thin_Man_plutonium_gun_bomb_casings.jpg" decoding="async" width="220" height="127" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Thin_Man_plutonium_gun_bomb_casings.jpg/330px-Thin_Man_plutonium_gun_bomb_casings.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Thin_Man_plutonium_gun_bomb_casings.jpg/440px-Thin_Man_plutonium_gun_bomb_casings.jpg 2x" data-file-width="898" data-file-height="520" /></a><figcaption>A row of <a href="/wiki/Thin_Man_(nuclear_bomb)" title="Thin Man (nuclear bomb)">Thin Man</a> casings. <a href="/wiki/Fat_Man" title="Fat Man">Fat Man</a> casings are visible in the background. The tow truck was used by the <a href="/wiki/216th_Army_Air_Forces_Base_Unit" title="216th Army Air Forces Base Unit">216th Army Air Forces Base Unit</a> to move them.</figcaption></figure> <p>A proving ground was established at the Anchor Ranch. The gun would be an unusual one, and it had to be designed in the absence of crucial data about the critical mass. The design criteria were that the gun would have a muzzle velocity of 3,000 feet per second (910&#160;m/s); that the tube would weigh only 1 short ton (0.91&#160;t) instead of the conventional 5 short tons (4.5&#160;t) for a tube with that energy; that, as a consequence it would be made of alloyed steel; that it should have a maximum breech pressure of 75,000 <a href="/wiki/Pound_per_square_inch" title="Pound per square inch">pounds per square inch</a> (520,000&#160;<a href="/wiki/Pascal_(unit)" title="Pascal (unit)">kPa</a>); and that it should have three independent <a href="/wiki/Primer_(firearm)" class="mw-redirect" title="Primer (firearm)">primers</a>. Because it would need to be fired only once, the barrel could be made lighter than the conventional gun.<sup id="cite_ref-119" class="reference"><a href="#cite_note-119"><span class="cite-bracket">&#91;</span>119<span class="cite-bracket">&#93;</span></a></sup> Nor did it require <a href="/wiki/Rifling" title="Rifling">rifling</a> or recoil mechanisms. Pressure curves were computed under Hirschfelder's supervision at the <a href="/wiki/Geophysical_Laboratory" class="mw-redirect" title="Geophysical Laboratory">Geophysical Laboratory</a> prior to his joining the Los Alamos Laboratory.<sup id="cite_ref-FOOTNOTEHawkins1961127–128_120-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961127–128-120"><span class="cite-bracket">&#91;</span>120<span class="cite-bracket">&#93;</span></a></sup> </p><p>While they waited for the guns to be fabricated by the <a href="/wiki/Naval_Gun_Factory" class="mw-redirect" title="Naval Gun Factory">Naval Gun Factory</a>, various propellants were tested. Hirschfelder sent John L. Magee to the <a href="/wiki/United_States_Bureau_of_Mines" title="United States Bureau of Mines">Bureau of Mines</a>' <a href="/wiki/Experimental_Mine,_U.S._Bureau_of_Mines" title="Experimental Mine, U.S. Bureau of Mines">Experimental Mine</a> at <a href="/wiki/Bruceton,_Pennsylvania" title="Bruceton, Pennsylvania">Bruceton, Pennsylvania</a> to test the propellant and ignition system.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993114–115_121-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993114–115-121"><span class="cite-bracket">&#91;</span>121<span class="cite-bracket">&#93;</span></a></sup> Test firing was conducted at the Anchor Ranch with a <a href="/wiki/3%22/50_caliber_gun" class="mw-redirect" title="3&quot;/50 caliber gun">3-inch (76&#160;mm)/50 caliber gun</a>. This allowed the fine-tuning of the testing instrumentation. The first two tubes arrived at Los Alamos on 10 March 1944, and test firing began at the Anchor Ranch under the direction of Thomas H. Olmstead, who had experience in such work at the <a href="/wiki/Naval_Surface_Warfare_Center_Dahlgren_Division" title="Naval Surface Warfare Center Dahlgren Division">Naval Proving Ground</a> in <a href="/wiki/Dahlgren,_Virginia" title="Dahlgren, Virginia">Dahlgren, Virginia</a>. The primers were tested and found to work at pressures up to 80,000 pounds per square inch (550,000&#160;kPa). Brode's group investigated the fusing systems, testing <a href="/wiki/Radar_altimeter" title="Radar altimeter">radar altimeters</a>, <a href="/wiki/Proximity_fuse" class="mw-redirect" title="Proximity fuse">proximity fuses</a> and <a href="/wiki/Barometric_altimeter" class="mw-redirect" title="Barometric altimeter">barometric altimeter</a> fuses.<sup id="cite_ref-FOOTNOTEHawkins1961129–134_122-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961129–134-122"><span class="cite-bracket">&#91;</span>122<span class="cite-bracket">&#93;</span></a></sup> </p><p>Tests were conducted with a <a href="/wiki/Frequency-modulated_continuous-wave_radar" class="mw-redirect" title="Frequency-modulated continuous-wave radar">frequency modulated</a> type radar altimeter known as AYD and a pulse type known as 718. The AYD modifications were made by the Norden Laboratories Corporation under an OSRD contract. When the manufacturer of 718, <a href="/wiki/RCA" title="RCA">RCA</a>, was contacted, it was learned that a new <a href="/wiki/Tail_warning_radar" title="Tail warning radar">tail warning radar</a>, <a href="/wiki/AN/APS-13" class="mw-redirect" title="AN/APS-13">AN/APS-13</a>, later nicknamed <i>Archie</i>, was just entering production, which could be adapted for use as a radar altimeter. The third unit to be made was delivered to Los Alamos in April 1944. In May it was tested by diving an <a href="/wiki/Beechcraft_Model_18" title="Beechcraft Model 18">AT-11</a>. This was followed by full-scale drop testing in June and July. These were very successful, whereas the AYD continued to suffer from problems. Archie was therefore adopted, although the scarcity of units in August 1944 precluded wholescale destructive testing.<sup id="cite_ref-FOOTNOTEHawkins1961129–134_122-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961129–134-122"><span class="cite-bracket">&#91;</span>122<span class="cite-bracket">&#93;</span></a></sup> Testing of <a href="/wiki/Silverplate" title="Silverplate">Silverplate</a> <a href="/wiki/Boeing_B-29_Superfortress" title="Boeing B-29 Superfortress">Boeing B-29 Superfortress</a> aircraft with Thin Man bomb shapes was carried out at <a href="/wiki/Edwards_Air_Force_Base" title="Edwards Air Force Base">Muroc Army Air Field</a> in March and June 1944.<sup id="cite_ref-FOOTNOTERamsey2012344–345_123-0" class="reference"><a href="#cite_note-FOOTNOTERamsey2012344–345-123"><span class="cite-bracket">&#91;</span>123<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Plutonium">Plutonium</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=13" title="Edit section: Plutonium"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>At a meeting of the S-1 Executive Committee on 14 November 1942, Chadwick had expressed a fear that the <a href="/wiki/Alpha_particle" title="Alpha particle">alpha particles</a> emitted by plutonium could produce neutrons in light elements present as impurities, which in turn would produce fission in the plutonium and cause a <a href="/wiki/Fizzle_(nuclear_test)" class="mw-redirect" title="Fizzle (nuclear test)">predetonation</a>, a chain reaction before the core was fully assembled. This had been considered by Oppenheimer and Seaborg the month before, and the latter had calculated that neutron emitters like <a href="/wiki/Boron" title="Boron">boron</a> had to be restricted to one part in a hundred billion. There was some doubt about whether a chemical process could be developed that could ensure this level of purity, and Chadwick brought the matter to the S-1 Executive Committee's attention for it to be considered further. Four days later, though, Lawrence, Oppenheimer, Compton and McMillan reported to Conant that they had confidence that the exacting purity requirement could be met.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962109_124-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962109-124"><span class="cite-bracket">&#91;</span>124<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Plutonium_ring.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Plutonium_ring.jpg/220px-Plutonium_ring.jpg" decoding="async" width="220" height="209" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Plutonium_ring.jpg/330px-Plutonium_ring.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Plutonium_ring.jpg/440px-Plutonium_ring.jpg 2x" data-file-width="1295" data-file-height="1231" /></a><figcaption>A ring of electrorefined plutonium. It has a purity of 99.96%, weighs 5.3 kg, and is about 11&#160;cm in diameter. It is enough plutonium for one bomb core. The ring shape helps with criticality safety.</figcaption></figure> <p>Only microscopic quantities of plutonium were available until the <a href="/wiki/X-10_Graphite_Reactor" title="X-10 Graphite Reactor">X-10 Graphite Reactor</a> at the Clinton Engineer Works came online on 4 November 1943,<sup id="cite_ref-FOOTNOTEHewlettAnderson1962211_125-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962211-125"><span class="cite-bracket">&#91;</span>125<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEBakerHeckerHarbur1983141_126-0" class="reference"><a href="#cite_note-FOOTNOTEBakerHeckerHarbur1983141-126"><span class="cite-bracket">&#91;</span>126<span class="cite-bracket">&#93;</span></a></sup> but there were already some worrying signs. When <a href="/wiki/Plutonium_fluoride" title="Plutonium fluoride">plutonium fluoride</a> was produced at the Metallurgical Laboratory, it was sometimes light colored, and sometimes dark, although the chemical process was the same. When they managed to reduce it to plutonium metal in November 1943, the density was measured at 15&#160;g/cm<sup>3</sup>, and a measurement using <a href="/wiki/X-ray_scattering_techniques" title="X-ray scattering techniques">X-ray scattering techniques</a> pointed to a density of 13&#160;g/cm<sup>3</sup>. This was bad; it had been assumed that its density was the same as uranium, about 19&#160;g/cm<sup>3</sup>. If these figures were correct, far more plutonium would be needed for a bomb. Kennedy disliked Seaborg's ambitious and attention-seeking manner, and with <a href="/wiki/Arthur_Wahl" title="Arthur Wahl">Arthur Wahl</a> had devised a procedure for plutonium purification independent of Seaborg's group. When they got hold of a sample in February, this procedure was tested. That month the Metallurgical Laboratory announced that it had determined that there were two different fluorides: the light colored <a href="/wiki/Plutonium_tetrafluoride" title="Plutonium tetrafluoride">plutonium tetrafluoride</a> (PuF<sub>4</sub>) and the dark <a href="/wiki/Plutonium_trifluoride" class="mw-redirect" title="Plutonium trifluoride">plutonium trifluoride</a> (PuF<sub>3</sub>). The chemists soon discovered how to make them selectively, and the former turned out to be easier to reduce to metal. Measurements in March 1944 indicated a density of between 19 and 20&#160;g/cm<sup>3</sup>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993220–221_127-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993220–221-127"><span class="cite-bracket">&#91;</span>127<span class="cite-bracket">&#93;</span></a></sup> </p><p>Eric Jette's CM-8 (Plutonium Metallurgy) Group began experimenting with plutonium metal after gram quantities were received at the Los Alamos Laboratory in March 1944. By heating it, the metallurgists discovered five temperatures between 137 and 580&#160;°C (279 and 1,076&#160;°F) at which it suddenly started absorbing heat without increasing in temperature. This was a strong indication of multiple <a href="/wiki/Allotropes_of_plutonium" title="Allotropes of plutonium">allotropes of plutonium</a>; but was initially considered too bizarre to be true. Further testing confirmed a state change around 135&#160;°C (275&#160;°F); it entered the δ phase, with a density of 16&#160;g/cm<sup>3</sup>. Seaborg had claimed that plutonium had a melting point of around 950 to 1,000&#160;°C (1,740 to 1,830&#160;°F), about that of uranium, but the metallurgists at the Los Alamos Laboratory soon discovered that it melted at around 635&#160;°C (1,175&#160;°F). The chemists then turned to techniques for removing light element impurities from the plutonium; but on 14 July 1944, Oppenheimer informed Kennedy that this would no longer be required.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993223–227_128-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993223–227-128"><span class="cite-bracket">&#91;</span>128<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Plutonium_density-eng.svg" class="mw-file-description"><img alt="A graph showing change in density with increasing temperature upon sequential phase transitions between alpha, beta, gamma, delta, delta&#39; and epsilon phases" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Plutonium_density-eng.svg/220px-Plutonium_density-eng.svg.png" decoding="async" width="220" height="157" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Plutonium_density-eng.svg/330px-Plutonium_density-eng.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4f/Plutonium_density-eng.svg/440px-Plutonium_density-eng.svg.png 2x" data-file-width="1611" data-file-height="1153" /></a><figcaption>Plutonium has six <a href="/wiki/Allotrope" class="mw-redirect" title="Allotrope">allotropes</a> at ambient pressure: <b>alpha</b>&#160;(α), <b>beta</b>&#160;(β), <b>gamma</b>&#160;(γ), <b>delta</b>&#160;(δ), <b>delta&#160;prime</b>&#160;(δ'), &amp; <b>epsilon</b>&#160;(ε) <sup id="cite_ref-FOOTNOTEBakerHeckerHarbur1983146_129-0" class="reference"><a href="#cite_note-FOOTNOTEBakerHeckerHarbur1983146-129"><span class="cite-bracket">&#91;</span>129<span class="cite-bracket">&#93;</span></a></sup></figcaption></figure> <p>The notion of <a href="/wiki/Spontaneous_fission" title="Spontaneous fission">spontaneous fission</a> had been raised by Niels Bohr and <a href="/wiki/John_Archibald_Wheeler" title="John Archibald Wheeler">John Archibald Wheeler</a> in their 1939 treatment of the mechanism of nuclear fission.<sup id="cite_ref-130" class="reference"><a href="#cite_note-130"><span class="cite-bracket">&#91;</span>130<span class="cite-bracket">&#93;</span></a></sup> The first attempt to discover spontaneous fission in uranium was made by <a href="/wiki/Willard_Libby" title="Willard Libby">Willard Libby</a>, but he failed to detect it.<sup id="cite_ref-131" class="reference"><a href="#cite_note-131"><span class="cite-bracket">&#91;</span>131<span class="cite-bracket">&#93;</span></a></sup> It had been observed in Britain by Frisch and Titterton, and independently in the <a href="/wiki/Soviet_Union" title="Soviet Union">Soviet Union</a> by <a href="/wiki/Georgy_Flyorov" title="Georgy Flyorov">Georgy Flyorov</a> and <a href="/wiki/Konstantin_Petrzhak" title="Konstantin Petrzhak">Konstantin Petrzhak</a> in 1940; the latter are generally credited with the discovery.<sup id="cite_ref-FOOTNOTEFrisch1979129_132-0" class="reference"><a href="#cite_note-FOOTNOTEFrisch1979129-132"><span class="cite-bracket">&#91;</span>132<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-133" class="reference"><a href="#cite_note-133"><span class="cite-bracket">&#91;</span>133<span class="cite-bracket">&#93;</span></a></sup> Compton had also heard from the French physicist <a href="/wiki/Pierre_Victor_Auger" title="Pierre Victor Auger">Pierre Auger</a> that <a href="/wiki/Fr%C3%A9d%C3%A9ric_Joliot-Curie" title="Frédéric Joliot-Curie">Frédéric Joliot-Curie</a> had detected what might have been spontaneous fission in <a href="/wiki/Polonium" title="Polonium">polonium</a>. If true, it might preclude the use of polonium in the neutron initiators; if true for plutonium, it might mean that the gun-type design would not work. The consensus at the Los Alamos Laboratory was that it was not true, and that Joliot-Curie's results had been distorted by impurities.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962250–251_134-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962250–251-134"><span class="cite-bracket">&#91;</span>134<span class="cite-bracket">&#93;</span></a></sup> </p><p>At the Los Alamos Laboratory, Emilio Segrè's P-5 (Radioactivity) Group set out to measure it in <a href="/wiki/Uranium-234" title="Uranium-234">uranium-234</a>, −235 and −238, plutonium, polonium, <a href="/wiki/Protactinium" title="Protactinium">protactinium</a> and <a href="/wiki/Thorium" title="Thorium">thorium</a>.<sup id="cite_ref-135" class="reference"><a href="#cite_note-135"><span class="cite-bracket">&#91;</span>135<span class="cite-bracket">&#93;</span></a></sup> They were not too worried about the plutonium itself; their main concern was the issue Chadwick had raised about interaction with light element impurities. Segrè and his group of young physicists set up their experiment in an old Forest Service log cabin in Pajarito Canyon, about 14 miles (23&#160;km) from the Technical Area, in order to minimize background radiation emanating for other research at the Los Alamos Laboratory.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993229–233_136-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993229–233-136"><span class="cite-bracket">&#91;</span>136<span class="cite-bracket">&#93;</span></a></sup> </p><p>By August 1943, they had good values for all the elements tested except for plutonium, which they were unable to measure accurately enough because the only sample they had was five 20 μg samples created by the 60-inch cyclotron at Berkeley.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–237_137-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–237-137"><span class="cite-bracket">&#91;</span>137<span class="cite-bracket">&#93;</span></a></sup> They did observe that measurements taken at Los Alamos were greater than those made at Berkeley, which they attributed to <a href="/wiki/Cosmic_rays" class="mw-redirect" title="Cosmic rays">cosmic rays</a>, which are more numerous at Los Alamos, which is 7,300 feet (2,200&#160;m) above sea level.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962241_138-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962241-138"><span class="cite-bracket">&#91;</span>138<span class="cite-bracket">&#93;</span></a></sup> While their measurements indicated a spontaneous fission rate of 40 fissions per gram per hour, which was high but acceptable, the error margin was unacceptably large. In April 1944 they received a sample from the X-10 Graphite Reactor. Tests soon indicated 180 fissions per gram per hour, which was unacceptably high. It fell to Bacher to inform Compton, who was visibly shaken.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–239_139-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–239-139"><span class="cite-bracket">&#91;</span>139<span class="cite-bracket">&#93;</span></a></sup> Suspicion fell on <a href="/wiki/Plutonium-240" title="Plutonium-240">plutonium-240</a>, an isotope that had not yet been discovered, but whose existence had been suspected, it being simply created by a plutonium-239 nucleus absorbing a neutron. What had not been suspected was its high spontaneous fission rate. Segrè's group measured it at 1.6 million fissions per gram per hour, compared with just 40 per gram per hour for plutonium-239. <sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993243–245_140-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993243–245-140"><span class="cite-bracket">&#91;</span>140<span class="cite-bracket">&#93;</span></a></sup> This meant that reactor-bred plutonium was unsuitable for use in a gun-type weapon. The plutonium-240 would start the chain reaction too quickly, causing a predetonation that would release enough energy to disperse the critical mass before enough plutonium reacted. A faster gun was suggested but found to be impractical. So too was the possibility of separating the isotopes, as plutonium-240 is even harder to separate from plutonium-239 than uranium-235 from uranium-238.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993242–244_141-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993242–244-141"><span class="cite-bracket">&#91;</span>141<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Implosion-type_weapon_design">Implosion-type weapon design</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=14" title="Edit section: Implosion-type weapon design"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Implosion_bomb_animated.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Implosion_bomb_animated.gif/220px-Implosion_bomb_animated.gif" decoding="async" width="220" height="215" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/e/e0/Implosion_bomb_animated.gif 1.5x" data-file-width="300" data-file-height="293" /></a><figcaption>Explosive lenses are used to compress a fissile core inside an implosion-type nuclear weapon.</figcaption></figure> <p>Work on an alternative method of bomb design, known as implosion, had begun by Neddermeyer's E-5 (Implosion) group. Serber and Tolman had conceived implosion during the April 1943 conferences as a means of assembling pieces of fissionable material together to form a critical mass. Neddermeyer took a different tack, attempting to crush a hollow cylinder into a solid bar.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90_142-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90-142"><span class="cite-bracket">&#91;</span>142<span class="cite-bracket">&#93;</span></a></sup> The idea was to use explosives to crush a subcritical amount of fissile material into a smaller and denser form. When the fissile atoms are packed closer together, the rate of neutron capture increases, and they form a critical mass. The metal needs to travel only a very short distance, so the critical mass is assembled in much less time than it would take with the gun method.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962312–313_143-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962312–313-143"><span class="cite-bracket">&#91;</span>143<span class="cite-bracket">&#93;</span></a></sup> At the time, the idea of using explosives in this manner was quite novel. To facilitate the work, a small plant was established at the Anchor Ranch for casting explosive shapes.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90_142-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90-142"><span class="cite-bracket">&#91;</span>142<span class="cite-bracket">&#93;</span></a></sup> </p><p>Throughout 1943, implosion was considered a backup project in case the gun-type proved impractical for some reason.<sup id="cite_ref-FOOTNOTEHawkins196174_144-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196174-144"><span class="cite-bracket">&#91;</span>144<span class="cite-bracket">&#93;</span></a></sup> Theoretical physicists like Bethe, Oppenheimer and Teller were intrigued by the idea of a design of an atomic bomb that made more efficient use of fissile material, and permitted the use of material of lower purity. These were advantages of particular attraction to Groves. But while Neddermeyer's 1943 and early 1944 investigations into implosion showed promise, it was clear that the problem would be much more difficult from a theoretical and engineering perspective than the gun design. In July 1943, Oppenheimer wrote to John von Neumann, asking for his help, and suggesting that he visit Los Alamos where he could get "a better idea of this somewhat <a href="/wiki/Buck_Rogers" title="Buck Rogers">Buck Rogers</a> project".<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993129–130_145-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993129–130-145"><span class="cite-bracket">&#91;</span>145<span class="cite-bracket">&#93;</span></a></sup> </p><p>At the time, von Neumann was working for the Navy <a href="/wiki/Bureau_of_Ordnance" title="Bureau of Ordnance">Bureau of Ordnance</a>, Princeton University, the Army's <a href="/wiki/Aberdeen_Proving_Ground" title="Aberdeen Proving Ground">Aberdeen Proving Ground</a> and the NDRC. Oppenheimer, Groves and Parsons appealed to Tolman and <a href="/wiki/Rear_Admiral_(United_States)" class="mw-redirect" title="Rear Admiral (United States)">Rear Admiral</a> <a href="/wiki/William_R._Purnell" title="William R. Purnell">William R. Purnell</a> to release von Neumann. He visited Los Alamos from 20 September to 4 October 1943. Drawing on his recent work with <a href="/wiki/Blast_wave" title="Blast wave">blast waves</a> and <a href="/wiki/Shaped_charge" title="Shaped charge">shaped charges</a> used in armor-piercing shells, he suggested using a high-explosive shaped charge to implode a spherical core. A meeting of the Governing Board on 23 September resolved to approach George Kistiakowsky, a renowned expert on explosives then working for OSRD, to join the Los Alamos Laboratory.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993130–133_146-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993130–133-146"><span class="cite-bracket">&#91;</span>146<span class="cite-bracket">&#93;</span></a></sup> Although reluctant, he did so in November. He became a full-time staff member on 16 February 1944, becoming Parsons' deputy for implosion; McMillan became his deputy for the gun-type. The maximum size of the bomb was determined at this time from the size of the 5-by-12-foot (1.5 by 3.7&#160;m) bomb bay of the B-29.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993137–139_147-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993137–139-147"><span class="cite-bracket">&#91;</span>147<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Implosion_nuclear_weapon_design3.gif" class="mw-file-description"><img alt="Diagram showing fast explosive, slow explosive, uranium tamper, plutonium core and neutron initiator." src="//upload.wikimedia.org/wikipedia/commons/5/5c/Implosion_nuclear_weapon_design3.gif" decoding="async" width="200" height="200" class="mw-file-element" data-file-width="200" data-file-height="200" /></a><figcaption>An implosion-type nuclear bomb. In the center is the <a href="/wiki/Neutron_initiator" class="mw-redirect" title="Neutron initiator">neutron initiator</a> (red). It is surrounded by the plutonium hemispheres. There is a small air gap (white, not in the original Fat Man design) and then the uranium tamper. Around that is the aluminium pusher (purple). This is encased in the explosive lenses (gold). Colors are the same as in the diagram opposite. </figcaption></figure> <p>By July 1944, Oppenheimer had concluded that plutonium could not be used in a gun design. On July 18, he wrote to Groves that "at the present time the method to which an over-riding priority must be assigned is the method of implosion."<sup id="cite_ref-148" class="reference"><a href="#cite_note-148"><span class="cite-bracket">&#91;</span>148<span class="cite-bracket">&#93;</span></a></sup> The accelerated effort on an implosion design, codenamed <a href="/wiki/Fat_Man" title="Fat Man">Fat Man</a>, began in August 1944 when Oppenheimer implemented a sweeping reorganization of the Los Alamos laboratory to focus on implosion.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245–248_149-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245–248-149"><span class="cite-bracket">&#91;</span>149<span class="cite-bracket">&#93;</span></a></sup> Two new groups were created at Los Alamos to develop the implosion weapon, X (for explosives) Division headed by Kistiakowsky and G (for gadget) Division under Robert Bacher.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962311_150-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962311-150"><span class="cite-bracket">&#91;</span>150<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245_151-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245-151"><span class="cite-bracket">&#91;</span>151<span class="cite-bracket">&#93;</span></a></sup> Although Teller was head of the T-1 (Implosion and Super) Group, Bethe considered that Teller was spending too much time on the Super, which had been given a low priority by Bethe and Oppenheimer. In June 1944, Oppenheimer created a dedicated Super Group under Teller, who was made directly responsible to Oppenheimer, and Peierls became head of the T-1 (Implosion) Group.<sup id="cite_ref-FOOTNOTEHawkins196184_152-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196184-152"><span class="cite-bracket">&#91;</span>152<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993162_153-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993162-153"><span class="cite-bracket">&#91;</span>153<span class="cite-bracket">&#93;</span></a></sup> In September, Teller's group became the F-1 (Super and General Theory) Group, part of the Enrico Fermi's new F (Fermi) Division.<sup id="cite_ref-FOOTNOTEHawkins1961214–215_154-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961214–215-154"><span class="cite-bracket">&#91;</span>154<span class="cite-bracket">&#93;</span></a></sup> </p><p>The new design that von Neumann and T Division, most notably Rudolf Peierls, devised used <a href="/wiki/Explosive_lens" title="Explosive lens">explosive lenses</a> to focus the explosion onto a spherical shape using a combination of both slow and fast high explosives.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296_155-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296-155"><span class="cite-bracket">&#91;</span>155<span class="cite-bracket">&#93;</span></a></sup> A visit by Sir Geoffrey Taylor in May 1944 raised questions about the stability of the interface between the core and the <a href="/wiki/Depleted_uranium" title="Depleted uranium">depleted uranium</a> tamper. As a result, the design was made more conservative. The ultimate expression of this was the adoption of Christy's proposal that the core be solid instead of hollow.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993161,_270–271,_307–308_156-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993161,_270–271,_307–308-156"><span class="cite-bracket">&#91;</span>156<span class="cite-bracket">&#93;</span></a></sup> The design of lenses that detonated with the proper shape and velocity turned out to be slow, difficult and frustrating.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296_155-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296-155"><span class="cite-bracket">&#91;</span>155<span class="cite-bracket">&#93;</span></a></sup> Various explosives were tested before settling on <a href="/wiki/Composition_B" title="Composition B">composition B</a> as the fast explosive and <a href="/wiki/Baratol" title="Baratol">baratol</a> as the slow explosive.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993299_157-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993299-157"><span class="cite-bracket">&#91;</span>157<span class="cite-bracket">&#93;</span></a></sup> The final design resembled a soccer ball, with 20 hexagonal and 12 pentagonal lenses, each weighing about 80 pounds (36&#160;kg). Getting the detonation just right required fast, reliable and safe electrical <a href="/wiki/Detonator" title="Detonator">detonators</a>, of which there were two for each lens for reliability.<sup id="cite_ref-FOOTNOTEHansen1995bV-123_158-0" class="reference"><a href="#cite_note-FOOTNOTEHansen1995bV-123-158"><span class="cite-bracket">&#91;</span>158<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTERhodes1995195_159-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1995195-159"><span class="cite-bracket">&#91;</span>159<span class="cite-bracket">&#93;</span></a></sup> It was therefore decided to use <a href="/wiki/Exploding-bridgewire_detonator" title="Exploding-bridgewire detonator">exploding-bridgewire detonators</a>, a new invention developed at Los Alamos by a group led by <a href="/wiki/Luis_Walter_Alvarez" title="Luis Walter Alvarez">Luis Alvarez</a>. A contract for their manufacture was given to <a href="/wiki/Raytheon" title="Raytheon">Raytheon</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993301–307_160-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993301–307-160"><span class="cite-bracket">&#91;</span>160<span class="cite-bracket">&#93;</span></a></sup> </p><p>To study the behavior of converging <a href="/wiki/Shock_wave" title="Shock wave">shock waves</a>, Robert Serber devised the <a href="/wiki/RaLa_Experiment" title="RaLa Experiment">RaLa Experiment</a>, which used the short-lived <a href="/wiki/Radioisotope" class="mw-redirect" title="Radioisotope">radioisotope</a> <a href="/wiki/Lanthanum-140" class="mw-redirect" title="Lanthanum-140">lanthanum-140</a>, a potent source of <a href="/wiki/Gamma_radiation" class="mw-redirect" title="Gamma radiation">gamma radiation</a>. The gamma ray source was placed in the center of a metal sphere surrounded by the explosive lenses, which in turn were inside in an <a href="/wiki/Ionization_chamber" title="Ionization chamber">ionization chamber</a>. This allowed the taking of an X-ray movie of the implosion. The lenses were designed primarily using this series of tests.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993148–154_161-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993148–154-161"><span class="cite-bracket">&#91;</span>161<span class="cite-bracket">&#93;</span></a></sup> In his history of the Los Alamos project, <a href="/wiki/David_Hawkins_(philosopher)" title="David Hawkins (philosopher)">David Hawkins</a> wrote: "RaLa became the most important single experiment affecting the final bomb design".<sup id="cite_ref-FOOTNOTEHawkins1961203_162-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961203-162"><span class="cite-bracket">&#91;</span>162<span class="cite-bracket">&#93;</span></a></sup> </p><p>Within the explosives was the 4.5-inch (110&#160;mm) thick aluminum pusher, which provided a smooth transition from the relatively low density explosive to the next layer, the 3-inch (76&#160;mm) thick tamper of natural uranium. Its main job was to hold the critical mass together as long as possible, but it would also reflect neutrons back into the core. Some part of it might fission as well. To prevent predetonation by an external neutron, the tamper was coated in a thin layer of boron.<sup id="cite_ref-FOOTNOTEHansen1995bV-123_158-1" class="reference"><a href="#cite_note-FOOTNOTEHansen1995bV-123-158"><span class="cite-bracket">&#91;</span>158<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:HD.4G.053_(10540204545).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d0/HD.4G.053_%2810540204545%29.jpg/220px-HD.4G.053_%2810540204545%29.jpg" decoding="async" width="220" height="173" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d0/HD.4G.053_%2810540204545%29.jpg/330px-HD.4G.053_%2810540204545%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d0/HD.4G.053_%2810540204545%29.jpg/440px-HD.4G.053_%2810540204545%29.jpg 2x" data-file-width="5573" data-file-height="4389" /></a><figcaption>Norris Bradbury, group leader for bomb assembly, stands next to the partially assembled Gadget atop the Trinity test tower. Later, he became the director of Los Alamos vice Oppenheimer.</figcaption></figure> <p>A polonium-beryllium <a href="/wiki/Modulated_neutron_initiator" title="Modulated neutron initiator">modulated neutron initiator</a>, known as an "urchin" because its shape resembled the inner shell of a <a href="/wiki/Sea_urchin" title="Sea urchin">sea urchin</a>,<sup id="cite_ref-FOOTNOTEHansen1995aI-298_163-0" class="reference"><a href="#cite_note-FOOTNOTEHansen1995aI-298-163"><span class="cite-bracket">&#91;</span>163<span class="cite-bracket">&#93;</span></a></sup> was developed to start the chain reaction at precisely the right moment.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962235_164-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962235-164"><span class="cite-bracket">&#91;</span>164<span class="cite-bracket">&#93;</span></a></sup> This work with the chemistry and metallurgy of radioactive polonium was directed by <a href="/wiki/Charles_Allen_Thomas" title="Charles Allen Thomas">Charles Allen Thomas</a> of the <a href="/wiki/Monsanto_Company" class="mw-redirect" title="Monsanto Company">Monsanto Company</a> and became known as the <a href="/wiki/Dayton_Project" title="Dayton Project">Dayton Project</a>.<sup id="cite_ref-FOOTNOTEGilbert19693–4_165-0" class="reference"><a href="#cite_note-FOOTNOTEGilbert19693–4-165"><span class="cite-bracket">&#91;</span>165<span class="cite-bracket">&#93;</span></a></sup> Testing required up to 500 <a href="/wiki/Curie_(unit)" title="Curie (unit)">curies</a> per month of polonium, which Monsanto was able to deliver.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993308–310_166-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993308–310-166"><span class="cite-bracket">&#91;</span>166<span class="cite-bracket">&#93;</span></a></sup> The whole assembly was encased in a <a href="/wiki/Duralumin" title="Duralumin">duralumin</a> bomb casing to protect it from bullets and flak.<sup id="cite_ref-FOOTNOTEHansen1995bV-123_158-2" class="reference"><a href="#cite_note-FOOTNOTEHansen1995bV-123-158"><span class="cite-bracket">&#91;</span>158<span class="cite-bracket">&#93;</span></a></sup> </p><p>The ultimate task of the metallurgists was to determine how to cast plutonium into a sphere. The brittle α phase that exists at room temperature changes to the plastic β phase at higher temperatures. Attention then shifted to the even more malleable δ phase that normally exists in the 300 to 450&#160;°C (572 to 842&#160;°F) range. It was found that this was stable at room temperature when alloyed with aluminum, but aluminum emits neutrons when bombarded with <a href="/wiki/Alpha_particles" class="mw-redirect" title="Alpha particles">alpha particles</a>, which would exacerbate the pre-ignition problem. The metallurgists then hit upon a <a href="/wiki/Plutonium%E2%80%93gallium_alloy" title="Plutonium–gallium alloy">plutonium–gallium alloy</a>, which stabilized the δ phase and could be <a href="/wiki/Hot_pressing" title="Hot pressing">hot pressed</a> into the desired spherical shape. As plutonium was found to corrode readily, the sphere was coated with nickel.<sup id="cite_ref-FOOTNOTEBakerHeckerHarbur1983144–145_167-0" class="reference"><a href="#cite_note-FOOTNOTEBakerHeckerHarbur1983144–145-167"><span class="cite-bracket">&#91;</span>167<span class="cite-bracket">&#93;</span></a></sup> </p><p>The work proved dangerous. By the end of the war, half the experienced chemists and metallurgists had to be removed from work with plutonium when unacceptably high levels of the element appeared in their urine.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993288_168-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993288-168"><span class="cite-bracket">&#91;</span>168<span class="cite-bracket">&#93;</span></a></sup> A minor fire at Los Alamos in January 1945 led to a fear that a fire in the plutonium laboratory might contaminate the whole town, and Groves authorized the construction of a new facility for plutonium chemistry and metallurgy, which became known as the DP-site.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993290_169-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993290-169"><span class="cite-bracket">&#91;</span>169<span class="cite-bracket">&#93;</span></a></sup> The hemispheres for the first plutonium <a href="/wiki/Pit_(nuclear_weapon)" title="Pit (nuclear weapon)">pit</a> (or core) were produced and delivered on 2 July 1945. Three more hemispheres followed on 23 July and were delivered three days later.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993330–331_170-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993330–331-170"><span class="cite-bracket">&#91;</span>170<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Little_Boy">Little Boy</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=15" title="Edit section: Little Boy"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Little_Boy" title="Little Boy">Little Boy</a></div> <p>Following Oppenheimer's reorganization of the Los Alamos Laboratory in July 1944, the work on the uranium gun-type weapon was concentrated in <a href="/wiki/Francis_Birch_(geophysicist)" title="Francis Birch (geophysicist)">Francis Birch</a>'s O-1 (Gun) Group.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993250_171-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993250-171"><span class="cite-bracket">&#91;</span>171<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins1961221_172-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961221-172"><span class="cite-bracket">&#91;</span>172<span class="cite-bracket">&#93;</span></a></sup> The concept was pursued so that in case of a failure to develop an implosion bomb, at least the enriched uranium could be used.<sup id="cite_ref-FOOTNOTEHawkins1961223_173-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961223-173"><span class="cite-bracket">&#91;</span>173<span class="cite-bracket">&#93;</span></a></sup> Henceforth the gun-type had to work with enriched uranium only, and this allowed the Thin Man design to be greatly simplified. A high-velocity gun was no longer required, and a simpler weapon could be substituted, one short enough to fit into a B-29 bomb bay. The new design was called <a href="/wiki/Little_Boy" title="Little Boy">Little Boy</a>.<sup id="cite_ref-FOOTNOTERhodes1986541_174-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986541-174"><span class="cite-bracket">&#91;</span>174<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:77-BT-173.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cb/77-BT-173.jpg/220px-77-BT-173.jpg" decoding="async" width="220" height="164" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cb/77-BT-173.jpg/330px-77-BT-173.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cb/77-BT-173.jpg/440px-77-BT-173.jpg 2x" data-file-width="900" data-file-height="672" /></a><figcaption>A Little Boy unit on Tinian connected to test equipment, possibly to test or charge components within the device</figcaption></figure> <p>After repeated slippages, the first shipment of slightly enriched uranium (13 to 15 percent uranium-235) arrived from Oak Ridge in March 1944. Shipments of <a href="/wiki/Highly_enriched_uranium" class="mw-redirect" title="Highly enriched uranium">highly enriched uranium</a> commenced in June 1944. Criticality experiments and the Water Boiler had priority, so the metallurgists did not receive any until August 1944. <sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993218–219_175-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993218–219-175"><span class="cite-bracket">&#91;</span>175<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEJones1985143_176-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985143-176"><span class="cite-bracket">&#91;</span>176<span class="cite-bracket">&#93;</span></a></sup> In the meantime, the CM Division experimented with <a href="/wiki/Uranium_hydride" title="Uranium hydride">uranium hydride</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–211_177-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–211-177"><span class="cite-bracket">&#91;</span>177<span class="cite-bracket">&#93;</span></a></sup> This was considered by T Division as a prospective active material. The idea was that the hydrogen's ability as a neutron moderator would compensate for the loss of efficiency, but, as Bethe later recalled, its efficiency was "negligible or less, as Feynman would say", and the idea was dropped by August 1944.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993181_178-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993181-178"><span class="cite-bracket">&#91;</span>178<span class="cite-bracket">&#93;</span></a></sup> </p><p><a href="/wiki/Frank_Spedding" title="Frank Spedding">Frank Spedding</a>'s <a href="/wiki/Ames_Project" title="Ames Project">Ames Project</a> had developed the <a href="/wiki/Ames_process" title="Ames process">Ames process</a>, a method of producing uranium metal on an industrial scale, but <a href="/wiki/Cyril_Stanley_Smith" title="Cyril Stanley Smith">Cyril Stanley Smith</a>,<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213_179-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213-179"><span class="cite-bracket">&#91;</span>179<span class="cite-bracket">&#93;</span></a></sup> the CM Division's associate leader in charge of metallurgy,<sup id="cite_ref-FOOTNOTEHawkins1961148_180-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961148-180"><span class="cite-bracket">&#91;</span>180<span class="cite-bracket">&#93;</span></a></sup> was concerned about using it with highly enriched uranium due to the danger of forming a critical mass. Highly enriched uranium was also far more valuable than natural uranium, and he wanted to avoid the loss of even a milligram. He recruited Richard D. Baker, a chemist who had worked with Spedding, and together they adapted the Ames Process for use at the Los Alamos laboratory.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213_179-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213-179"><span class="cite-bracket">&#91;</span>179<span class="cite-bracket">&#93;</span></a></sup> In February Baker and his group made twenty 360 gram reductions and twenty-seven 500 gram reductions with highly enriched <a href="/wiki/Uranium_tetrafluoride" title="Uranium tetrafluoride">uranium tetrafluoride</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993252_181-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993252-181"><span class="cite-bracket">&#91;</span>181<span class="cite-bracket">&#93;</span></a></sup> </p><p>Two types of gun design were produced: Type A was of high alloy steel, and Type B of more ordinary steel. Type B was chosen for production because it was lighter. The primers and propellant were the same as those previously chosen for Thin Man.<sup id="cite_ref-FOOTNOTEHawkins1961224–225_182-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961224–225-182"><span class="cite-bracket">&#91;</span>182<span class="cite-bracket">&#93;</span></a></sup> Scale test firing of the hollow projectile and target insert was conducted with the 3-inch/50 caliber gun and a <a href="/wiki/20_mm_Hispano_cannon" class="mw-redirect" title="20 mm Hispano cannon">20&#160;mm (0.79&#160;in) Hispano cannon</a>. Starting in December, test firing was done full-scale. Amazingly, the first test case produced turned out to be the best ever made. It was used in four test firings at the Anchor Ranch, and ultimately in the Little Boy used in the <a href="/wiki/Bombing_of_Hiroshima" class="mw-redirect" title="Bombing of Hiroshima">bombing of Hiroshima</a>. The design specifications were completed in February 1945, and contracts were let to build the components. Three different plants were used so that no one would have a copy of the complete design. The gun and breech were made by the Naval Gun Factory in Washington, D.C.; the target, case and some other components were by the Naval Ordnance Plant in <a href="/wiki/Center_Line,_Michigan" title="Center Line, Michigan">Center Line, Michigan</a>; and the tail fairing and mounting brackets by the Expert Tool and Die Company in <a href="/wiki/Detroit,_Michigan" class="mw-redirect" title="Detroit, Michigan">Detroit, Michigan</a>.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993257_183-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993257-183"><span class="cite-bracket">&#91;</span>183<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins1961224–225_182-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961224–225-182"><span class="cite-bracket">&#91;</span>182<span class="cite-bracket">&#93;</span></a></sup> </p><p>Birch's tidy schedule was disrupted in December by Groves, who ordered Oppenheimer to give priority to the gun-type over implosion, so that the weapon would be ready by 1 July 1945.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993255–256_184-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993255–256-184"><span class="cite-bracket">&#91;</span>184<span class="cite-bracket">&#93;</span></a></sup> The bomb, except for the uranium payload, was ready at the beginning of May 1945.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993262_185-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993262-185"><span class="cite-bracket">&#91;</span>185<span class="cite-bracket">&#93;</span></a></sup> The uranium-235 projectile was completed on 15 June, and the target on 24 July.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265-186"><span class="cite-bracket">&#91;</span>186<span class="cite-bracket">&#93;</span></a></sup> The target and bomb pre-assemblies (partly assembled bombs without the fissile components) left <a href="/wiki/Hunters_Point_Naval_Shipyard" title="Hunters Point Naval Shipyard">Hunters Point Naval Shipyard</a>, California, on 16 July aboard the <a href="/wiki/Cruiser" title="Cruiser">cruiser</a> <a href="/wiki/USS_Indianapolis_(CA-35)" title="USS Indianapolis (CA-35)">USS&#160;<i>Indianapolis</i></a>, arriving 26 July.<sup id="cite_ref-FOOTNOTECoster-Mullen201230_187-0" class="reference"><a href="#cite_note-FOOTNOTECoster-Mullen201230-187"><span class="cite-bracket">&#91;</span>187<span class="cite-bracket">&#93;</span></a></sup> The target inserts followed by air on 30 July.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265-186"><span class="cite-bracket">&#91;</span>186<span class="cite-bracket">&#93;</span></a></sup> </p><p>Although all of its components had been tested in target and drop tests,<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-2" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265-186"><span class="cite-bracket">&#91;</span>186<span class="cite-bracket">&#93;</span></a></sup> no full test of a gun-type nuclear weapon occurred before Hiroshima. There were several reasons for not testing a Little Boy type of device. Primarily, there was insufficient uranium-235.<sup id="cite_ref-FOOTNOTEHansen1995b111–112_188-0" class="reference"><a href="#cite_note-FOOTNOTEHansen1995b111–112-188"><span class="cite-bracket">&#91;</span>188<span class="cite-bracket">&#93;</span></a></sup> Additionally, the weapon design was simple enough that it was only deemed necessary to do laboratory tests with the gun-type assembly. Unlike the implosion design, which required sophisticated coordination of shaped explosive charges, the gun-type design was considered almost certain to work.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993293_189-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993293-189"><span class="cite-bracket">&#91;</span>189<span class="cite-bracket">&#93;</span></a></sup> Thirty-two drop tests were conducted at <a href="/wiki/Wendover_Air_Force_Base" title="Wendover Air Force Base">Wendover</a>, and only once did the bomb fail to fire. One last-minute modification was made, to allow the powder bags of propellant that fired the gun to be loaded in the bomb bay.<sup id="cite_ref-FOOTNOTEHawkins1961224–225_182-2" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961224–225-182"><span class="cite-bracket">&#91;</span>182<span class="cite-bracket">&#93;</span></a></sup> </p><p>The danger of accidental detonation made safety a concern. Little Boy incorporated basic safety mechanisms, but an accidental detonation could still occur. Tests were conducted to see whether a crash could drive the hollow "bullet" onto the "target" cylinder resulting in a massive release of radiation, or possibly nuclear detonation. These showed that this required an impact of 500 times that of gravity, which made it highly unlikely.<sup id="cite_ref-FOOTNOTEHansen1995b113_190-0" class="reference"><a href="#cite_note-FOOTNOTEHansen1995b113-190"><span class="cite-bracket">&#91;</span>190<span class="cite-bracket">&#93;</span></a></sup> There was still concern that a crash and a fire could trigger the explosives.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993333_191-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993333-191"><span class="cite-bracket">&#91;</span>191<span class="cite-bracket">&#93;</span></a></sup> If immersed in water, the uranium halves were subject to a <a href="/wiki/Neutron_moderator" title="Neutron moderator">neutron moderator</a> effect. While this would not have caused an explosion, it could have created widespread <a href="/wiki/Radioactive_contamination" title="Radioactive contamination">radioactive contamination</a>. For this reason, pilots were advised to crash on land rather than at sea.<sup id="cite_ref-FOOTNOTEHansen1995b113_190-1" class="reference"><a href="#cite_note-FOOTNOTEHansen1995b113-190"><span class="cite-bracket">&#91;</span>190<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Water_boiler">Water boiler</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=16" title="Edit section: Water boiler"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Los-Alamos-Water-Boiler-LANL12784.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Los-Alamos-Water-Boiler-LANL12784.jpg/220px-Los-Alamos-Water-Boiler-LANL12784.jpg" decoding="async" width="220" height="289" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Los-Alamos-Water-Boiler-LANL12784.jpg/330px-Los-Alamos-Water-Boiler-LANL12784.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/59/Los-Alamos-Water-Boiler-LANL12784.jpg/440px-Los-Alamos-Water-Boiler-LANL12784.jpg 2x" data-file-width="1352" data-file-height="1775" /></a><figcaption>Water Boiler</figcaption></figure> <p>The Water Boiler was an <a href="/wiki/Aqueous_homogeneous_reactor" title="Aqueous homogeneous reactor">aqueous homogeneous reactor</a>, a type of nuclear reactor in which the <a href="/wiki/Nuclear_fuel" title="Nuclear fuel">nuclear fuel</a> in the form of soluble <a href="/wiki/Uranium_sulfate" class="mw-redirect" title="Uranium sulfate">uranium sulfate</a> is <a href="/wiki/Dissolution_(chemistry)" class="mw-redirect" title="Dissolution (chemistry)">dissolved</a> in water.<sup id="cite_ref-FOOTNOTEBunker1983124–125_192-0" class="reference"><a href="#cite_note-FOOTNOTEBunker1983124–125-192"><span class="cite-bracket">&#91;</span>192<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins1961116–120_193-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961116–120-193"><span class="cite-bracket">&#91;</span>193<span class="cite-bracket">&#93;</span></a></sup> Uranium sulfate was chosen instead of <a href="/wiki/Uranium_nitrate" class="mw-redirect" title="Uranium nitrate">uranium nitrate</a> because sulfur's neutron capture cross section is less than that of nitrogen.<sup id="cite_ref-FOOTNOTEHawkins1961165–166_194-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961165–166-194"><span class="cite-bracket">&#91;</span>194<span class="cite-bracket">&#93;</span></a></sup> The project was proposed by Bacher in April 1943 as part of an ongoing program of measuring critical masses in chain-reacting systems. He saw it also as a means of testing various materials in critical mass systems. T Division were opposed to the project, which was seen as a distraction from studies related to the form of chain reactions found in an atomic bomb, but Bacher prevailed on this point.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203-195"><span class="cite-bracket">&#91;</span>195<span class="cite-bracket">&#93;</span></a></sup> Calculations related to the Water Boiler did take up an inordinate amount of T Division's time in 1943.<sup id="cite_ref-FOOTNOTEHawkins1961116–120_193-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961116–120-193"><span class="cite-bracket">&#91;</span>193<span class="cite-bracket">&#93;</span></a></sup> The reactor theory developed by Fermi did not apply to the Water Boiler.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199388_196-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199388-196"><span class="cite-bracket">&#91;</span>196<span class="cite-bracket">&#93;</span></a></sup> </p><p>Little was known about building reactors in 1943. A group was created in Bacher's P Division, the P-7 (Water Boiler) Group, under the leadership of <a href="/wiki/Donald_Kerst" class="mw-redirect" title="Donald Kerst">Donald Kerst</a>,<sup id="cite_ref-FOOTNOTEHawkins1961101_197-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961101-197"><span class="cite-bracket">&#91;</span>197<span class="cite-bracket">&#93;</span></a></sup> that included Charles P. Baker, <a href="/wiki/Gerhart_Friedlander" title="Gerhart Friedlander">Gerhart Friedlander</a>, <a href="/wiki/Lindsay_Helmholz" title="Lindsay Helmholz">Lindsay Helmholz</a>, Marshall Holloway and <a href="/wiki/Raemer_Schreiber" title="Raemer Schreiber">Raemer Schreiber</a>. Robert F. Christy from the T-1 Group provided support with the theoretical calculations, in particular, a calculation of the critical mass. He calculated that 600 grams of uranium-235 would form a critical mass in a tamper of infinite size. Initially it was planned to operate the Water Boiler at 10&#160;kW, but Fermi and <a href="/wiki/Samuel_K._Allison" class="mw-redirect" title="Samuel K. Allison">Samuel K. Allison</a> visited in September 1943, and went over the proposed design. They pointed out the danger of decomposition of the uranium salt, and recommended heavier shielding. It was also noted that radioactive <a href="/wiki/Fission_products" class="mw-redirect" title="Fission products">fission products</a> would be created that would have to be chemically removed. As a consequence, it was decided that the Water Boiler would only run at 1&#160;kW until more operating experience had been accumulated, and features needed for high power operation were shelved for the time being.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203-195"><span class="cite-bracket">&#91;</span>195<span class="cite-bracket">&#93;</span></a></sup> </p><p>Christy also calculated the area that would become contaminated if an accidental explosion occurred. A site in Los Alamos Canyon was selected that was a safe distance from the township and downstream from the water supply. Known as Omega, it was approved by the Governing Board on 19 August 1943. The Water Boiler was not simple to construct. The two halves of the 12.0625-inch (306.39&#160;mm) stainless steel sphere that was the boiler had to be <a href="/wiki/Arc_welding" title="Arc welding">arc welded</a> because <a href="/wiki/Solder" title="Solder">solder</a> would be corroded by the uranium salt. The CM-7 (Miscellaneous Metallurgy) Group produced <a href="/wiki/Beryllia" class="mw-redirect" title="Beryllia">beryllia</a> bricks for the Water Boiler's tamper in December 1943 and January 1944. They were hot pressed in <a href="/wiki/Graphite" title="Graphite">graphite</a> at 1,000&#160;°C (1,830&#160;°F) at 100 pounds per square inch (690&#160;kPa) for 5 to 20 minutes. Some 53 bricks were made, shaped to fit around the boiler. The building at Omega Site was ready, if incomplete, by 1 February 1944, and the Water Boiler was fully assembled by 1 April. Sufficient enriched uranium had arrived by May to start it up, and it went critical on 9 May 1944.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-2" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203-195"><span class="cite-bracket">&#91;</span>195<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHawkins1961162–163_198-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961162–163-198"><span class="cite-bracket">&#91;</span>198<span class="cite-bracket">&#93;</span></a></sup> It was only the third reactor in the world to do so, the first two being the <a href="/wiki/Chicago_Pile-1" title="Chicago Pile-1">Chicago Pile-1</a> reactor at the Metallurgical Laboratory and the X-10 Graphite Reactor at the Clinton Engineer Works.<sup id="cite_ref-FOOTNOTEBunker1983124–125_192-1" class="reference"><a href="#cite_note-FOOTNOTEBunker1983124–125-192"><span class="cite-bracket">&#91;</span>192<span class="cite-bracket">&#93;</span></a></sup> Improved cross-section measurements allowed Christy to refine his criticality estimate to 575 grams. In fact, only 565 grams were required. The accuracy of his prediction surprised Christy more than anyone.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-3" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203-195"><span class="cite-bracket">&#91;</span>195<span class="cite-bracket">&#93;</span></a></sup> </p><p>In September 1944, the P-7 (Water Boiler) Group became the F-2 (Water Boiler) Group, part of Fermi's F Division.<sup id="cite_ref-FOOTNOTEHawkins1961213_199-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961213-199"><span class="cite-bracket">&#91;</span>199<span class="cite-bracket">&#93;</span></a></sup> On completion of the planned series of experiments in June 1944, it was decided to rebuild it as a more powerful reactor. The original goal of 10&#160;kW power was discarded in favor of 5&#160;kW, which would keep the cooling requirements simple. It was estimated that it would have a <a href="/wiki/Neutron_flux" title="Neutron flux">neutron flux</a> of 5 x 10<sup>10</sup> neutrons per square centimeter per second. Water cooling was installed, along with additional control rods. This time uranium nitrate was used instead of uranium sulfate because the former could more easily be decontaminated. The tamper of beryllia bricks was surrounded with graphite blocks, as beryllia was hard to procure, and to avoid the (γ, n) reaction in the beryllium,<sup id="cite_ref-FOOTNOTEHawkins1961218–219_200-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961218–219-200"><span class="cite-bracket">&#91;</span>200<span class="cite-bracket">&#93;</span></a></sup> in which <a href="/wiki/Gamma_rays" class="mw-redirect" title="Gamma rays">gamma rays</a> produced by the reactor-generated neutrons:<sup id="cite_ref-201" class="reference"><a href="#cite_note-201"><span class="cite-bracket">&#91;</span>201<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span style="white-space:nowrap;"><a href="/wiki/Beryllium-9" class="mw-redirect" title="Beryllium-9"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">9</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sub></span></span>Be<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> + <span style="white-space:nowrap;"><a href="/wiki/Gamma_ray" title="Gamma ray"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>&#947;<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> → <span style="white-space:nowrap;"><a href="/wiki/Beryllium-8" title="Beryllium-8"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">8</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sub></span></span>Be<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> + <span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> - 1.66 <a href="/wiki/MeV" class="mw-redirect" title="MeV">MeV</a></dd></dl> <p>The reactor commenced operation in December 1944.<sup id="cite_ref-FOOTNOTEHawkins1961218–219_200-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961218–219-200"><span class="cite-bracket">&#91;</span>200<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Super">Super</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=17" title="Edit section: Super"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/History_of_the_Teller%E2%80%93Ulam_design" title="History of the Teller–Ulam design">History of the Teller–Ulam design</a></div> <p>From the first, research into the Super was directed by Teller, who was its most enthusiastic proponent. Although this work was always considered secondary to the objective of developing a fission bomb, the prospect of creating more powerful bombs was sufficient to keep it going. The Berkeley summer conference had convinced Teller that the Super was technologically feasible. An important contribution was made by <a href="/wiki/Emil_Konopinski" title="Emil Konopinski">Emil Konopinski</a>, who suggested that deuterium could more easily be ignited if it was mixed with tritium. Bethe noted that a tritium-deuterium (T-D) reaction releases five times as much energy as a deuterium-deuterium (D-D) reaction. This was not immediately followed up, because tritium was hard to obtain, and there were hopes that deuterium could be easily ignited by a fission bomb, but the cross sections of T-D and D-D were measured by Manley's group in Chicago and Holloway's at Purdue.<sup id="cite_ref-FOOTNOTEHawkins196195–98_202-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins196195–98-202"><span class="cite-bracket">&#91;</span>202<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Los_Alamos_colloquium.jpg" class="mw-file-description"><img alt="A group of men in shirtsleeves sitting on folding chairs" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Los_Alamos_colloquium.jpg/220px-Los_Alamos_colloquium.jpg" decoding="async" width="220" height="171" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Los_Alamos_colloquium.jpg/330px-Los_Alamos_colloquium.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Los_Alamos_colloquium.jpg/440px-Los_Alamos_colloquium.jpg 2x" data-file-width="3000" data-file-height="2331" /></a><figcaption>The April 1946 colloquium on the <a href="/wiki/History_of_the_Teller%E2%80%93Ulam_design" title="History of the Teller–Ulam design">Super</a>. In the front row are (left to right) <a href="/wiki/Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a>, <a href="/wiki/John_H._Manley" class="mw-redirect" title="John H. Manley">John Manley</a>, <a href="/wiki/Enrico_Fermi" title="Enrico Fermi">Enrico Fermi</a> and J. M. B. Kellogg. <a href="/wiki/Robert_Oppenheimer" class="mw-redirect" title="Robert Oppenheimer">Robert Oppenheimer</a>, in dark coat, is behind Manley; to Oppenheimer's left is <a href="/wiki/Richard_Feynman" title="Richard Feynman">Richard Feynman</a>. The Army officer on the left is Colonel <a href="/wiki/Oliver_Haywood" title="Oliver Haywood">Oliver Haywood</a>.</figcaption></figure> <p>By September 1943, the values of the D-D and T-D had been revised upwards, raising hopes that a fusion reaction could be started at lower temperatures. Teller was sufficiently optimistic about the Super, and sufficiently concerned about reports that the Germans were interested in deuterium, to ask the Governing Board to raise its priority. The board agreed to some extent, but ruled that only one person could be spared to work on it full-time. Oppenheimer designated Konopinski, who would spend the rest of the war working on it. Nonetheless, in February 1944, Teller added <a href="/wiki/Stanislaw_Ulam" class="mw-redirect" title="Stanislaw Ulam">Stanislaw Ulam</a>, Jane Roberg, <a href="/wiki/Geoffrey_Chew" title="Geoffrey Chew">Geoffrey Chew</a>, and Harold and Mary Argo to his T-1 Group. Ulam calculated the <a href="/wiki/Compton_scattering" title="Compton scattering">inverse Compton cooling</a>, while Roberg worked out the ignition temperature of T-D mixtures.<sup id="cite_ref-FOOTNOTEHawkins196195–98_202-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins196195–98-202"><span class="cite-bracket">&#91;</span>202<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204_203-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204-203"><span class="cite-bracket">&#91;</span>203<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Maria_Goeppert" class="mw-redirect" title="Maria Goeppert">Maria Goeppert</a> joined the group in February 1945.<sup id="cite_ref-FOOTNOTEDash1973296–299_204-0" class="reference"><a href="#cite_note-FOOTNOTEDash1973296–299-204"><span class="cite-bracket">&#91;</span>204<span class="cite-bracket">&#93;</span></a></sup> </p><p>Teller argued for an increase in resources for Super research on the basis that it appeared to be far more difficult than anticipated. The board declined to do so, on the grounds that it was unlikely to bear fruit before the war ended, but did not cut it entirely. Indeed, Oppenheimer asked Groves to breed some tritium from deuterium in the X-10 Graphite Reactor. For some months Teller and Bethe argued about the priority of the Super research. In June 1944, Oppenheimer removed Teller and his Super Group from Bethe's T Division and placed it directly under himself. In September, it became the F-1 (Super) Group in Fermi' s F Division.<sup id="cite_ref-FOOTNOTEHawkins196195–98_202-2" class="reference"><a href="#cite_note-FOOTNOTEHawkins196195–98-202"><span class="cite-bracket">&#91;</span>202<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204_203-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204-203"><span class="cite-bracket">&#91;</span>203<span class="cite-bracket">&#93;</span></a></sup> Over the following months, Super research continued unabated. It was calculated that burning 1 cubic meter (35&#160;cu&#160;ft) of liquid deuterium would release the energy of 10 megatonnes of TNT (42&#160;PJ), enough to devastate 1,000 square miles (2,600&#160;km<sup>2</sup>).<sup id="cite_ref-FOOTNOTEHawkins1961214–216_205-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961214–216-205"><span class="cite-bracket">&#91;</span>205<span class="cite-bracket">&#93;</span></a></sup> The Super Group was transferred back to T Division on 14 November 1945.<sup id="cite_ref-FOOTNOTETruslowSmith196160_206-0" class="reference"><a href="#cite_note-FOOTNOTETruslowSmith196160-206"><span class="cite-bracket">&#91;</span>206<span class="cite-bracket">&#93;</span></a></sup> </p><p>A colloquium on the Super was held at the Los Alamos Laboratory in April 1946 to review the work done during the war. Teller gave an outline of his "Classic Super" concept, and <a href="/wiki/Nicholas_Metropolis" title="Nicholas Metropolis">Nicholas Metropolis</a> and <a href="/wiki/Anthony_L._Turkevich" title="Anthony L. Turkevich">Anthony L. Turkevich</a> presented the results of calculations that had been made concerning thermonuclear reactions. The final report on the Super, issued in June and prepared by Teller and his group, remained upbeat about the prospect of the Super being successfully developed, although that impression was not universal among those present at the colloquium.<sup id="cite_ref-PBS_207-0" class="reference"><a href="#cite_note-PBS-207"><span class="cite-bracket">&#91;</span>207<span class="cite-bracket">&#93;</span></a></sup> Work had to be curtailed in June 1946 due to the loss of staff.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962631–632_208-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962631–632-208"><span class="cite-bracket">&#91;</span>208<span class="cite-bracket">&#93;</span></a></sup> By 1950, calculations would show that the Classic Super would not work; that it would not only be unable to sustain thermonuclear burning in the deuterium fuel, but would be unable to ignite it in the first place.<sup id="cite_ref-PBS_207-1" class="reference"><a href="#cite_note-PBS-207"><span class="cite-bracket">&#91;</span>207<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Trinity">Trinity</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=18" title="Edit section: Trinity"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Trinity_(nuclear_test)" title="Trinity (nuclear test)">Trinity (nuclear test)</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg/220px-Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg" decoding="async" width="220" height="174" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg/330px-Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg/440px-Trinity_Test_-_Vital_Components_are_loaded_at_the_old_McDonald_Ranch_for_the_trip_to_the_test_site.jpg 2x" data-file-width="5477" data-file-height="4334" /></a><figcaption>Herbert Lehr and <a href="/wiki/Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a> loading the assembled tamper plug containing the plutonium pit and initiator into a sedan for transport from the <a href="/wiki/McDonald_Ranch_House" title="McDonald Ranch House">McDonald Ranch House</a> to the Trinity shot tower</figcaption></figure> <p>Because of the complexity of an implosion-style weapon, it was decided that, despite the waste of fissile material, an initial test would be required. Groves approved the test, subject to the active material being recovered. Consideration was therefore given to a controlled fizzle, but Oppenheimer opted instead for a full-scale <a href="/wiki/Nuclear_test" class="mw-redirect" title="Nuclear test">nuclear test</a>, codenamed "Trinity".<sup id="cite_ref-FOOTNOTEJones1985465_209-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985465-209"><span class="cite-bracket">&#91;</span>209<span class="cite-bracket">&#93;</span></a></sup> In March 1944, responsibility for planning the test was assigned to Kenneth Bainbridge, a professor of physics at Harvard, working under Kistiakowsky. Bainbridge selected the <a href="/wiki/Alamogordo_Bombing_Range" class="mw-redirect" title="Alamogordo Bombing Range">bombing range</a> near <a href="/wiki/Alamogordo_Army_Airfield" class="mw-redirect" title="Alamogordo Army Airfield">Alamogordo Army Airfield</a> as the site for the test.<sup id="cite_ref-FOOTNOTEHewlettAnderson1962318–319_210-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettAnderson1962318–319-210"><span class="cite-bracket">&#91;</span>210<span class="cite-bracket">&#93;</span></a></sup> Bainbridge worked with Captain Samuel P. Davalos on the construction of the Trinity Base Camp and its facilities, which included barracks, warehouses, workshops, an explosive <a href="/wiki/Magazine_(artillery)" title="Magazine (artillery)">magazine</a> and a <a href="/wiki/Commissary_(store)" title="Commissary (store)">commissary</a>.<sup id="cite_ref-FOOTNOTEJones1985478–481_211-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985478–481-211"><span class="cite-bracket">&#91;</span>211<span class="cite-bracket">&#93;</span></a></sup> </p><p>Groves did not relish the prospect of explaining the loss of a billion dollars worth of plutonium to a Senate committee, so a cylindrical containment vessel codenamed "Jumbo" was constructed to recover the active material in the event of a failure. Measuring 25 feet (7.6&#160;m) long and 12 feet (3.7&#160;m) wide, it was fabricated at great expense from 214 long tons (217&#160;t) of iron and steel by <a href="/wiki/Babcock_%26_Wilcox" title="Babcock &amp; Wilcox">Babcock &amp; Wilcox</a> in Barberton, Ohio. Brought in a special railroad car to a siding in Pope, New Mexico, it was transported the last 25 miles (40&#160;km) to the test site on a trailer pulled by two tractors.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993174–175_212-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993174–175-212"><span class="cite-bracket">&#91;</span>212<span class="cite-bracket">&#93;</span></a></sup> By the time it arrived, confidence in the implosion method was high enough, and the availability of plutonium was sufficient, that Oppenheimer decided not to use it. Instead, it was placed atop a steel tower 800 yards (730&#160;m) from the weapon as a rough measure of how powerful the explosion would be. In the end, Jumbo survived, although its tower did not, adding credence to the belief that Jumbo would have successfully contained a fizzled explosion.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993365–367_213-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993365–367-213"><span class="cite-bracket">&#91;</span>213<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEJones1985512_214-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985512-214"><span class="cite-bracket">&#91;</span>214<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Trinity_device_readied.jpg" class="mw-file-description"><img alt="Men stand around a large oil-rig type structure. A large round object is being hoisted up." src="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Trinity_device_readied.jpg/220px-Trinity_device_readied.jpg" decoding="async" width="220" height="174" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Trinity_device_readied.jpg/330px-Trinity_device_readied.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/88/Trinity_device_readied.jpg/440px-Trinity_device_readied.jpg 2x" data-file-width="5520" data-file-height="4371" /></a><figcaption>The explosives of "the gadget" were raised to the top of the tower for the final assembly.</figcaption></figure> <p>A pre-test explosion was conducted on 7 May 1945 to calibrate the instruments. A wooden test platform was erected 800 yards (730&#160;m) from Ground Zero and piled with 108 short tons (98&#160;t) of TNT spiked with <a href="/wiki/Nuclear_fission_product" title="Nuclear fission product">nuclear fission products</a> in the form of an irradiated uranium slug from the <a href="/wiki/Hanford_Site" title="Hanford Site">Hanford Site</a>, which was dissolved and poured into tubing inside the explosive. This explosion was observed by Oppenheimer and Groves's new deputy commander, Brigadier General <a href="/wiki/Thomas_Farrell_(general)" class="mw-redirect" title="Thomas Farrell (general)">Thomas Farrell</a>. The pre-test produced data that proved vital for the Trinity test.<sup id="cite_ref-FOOTNOTEJones1985512_214-1" class="reference"><a href="#cite_note-FOOTNOTEJones1985512-214"><span class="cite-bracket">&#91;</span>214<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993360–362_215-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993360–362-215"><span class="cite-bracket">&#91;</span>215<span class="cite-bracket">&#93;</span></a></sup> </p><p>For the actual test, the device, nicknamed "the gadget", was hoisted to the top of a 100-foot (30&#160;m) steel tower, as detonation at that height would give a better indication of how the weapon would behave when dropped from a bomber. Detonation in the air maximized the energy applied directly to the target, and generated less <a href="/wiki/Nuclear_fallout" title="Nuclear fallout">nuclear fallout</a>. The gadget was assembled under the supervision of <a href="/wiki/Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a> at the nearby <a href="/wiki/McDonald_Ranch_House" title="McDonald Ranch House">McDonald Ranch House</a> on 13 July, and precariously winched up the tower the following day.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993367–370_216-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993367–370-216"><span class="cite-bracket">&#91;</span>216<span class="cite-bracket">&#93;</span></a></sup> Observers included Bush, Chadwick, Conant, Farrell, Fermi, Groves, Lawrence, Oppenheimer and Tolman.<sup id="cite_ref-FOOTNOTEJones1985514–517_217-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985514–517-217"><span class="cite-bracket">&#91;</span>217<span class="cite-bracket">&#93;</span></a></sup> </p><p>At 05:30 on 16 July 1945 the gadget exploded with an <a href="/wiki/TNT_equivalent" title="TNT equivalent">energy equivalent</a> of around 20 kilotons of TNT, leaving a crater of <a href="/wiki/Trinitite" title="Trinitite">Trinitite</a> (radioactive glass) in the desert 250 feet (76&#160;m) wide. The shock wave was felt over 100 miles (160&#160;km) away, and the <a href="/wiki/Mushroom_cloud" title="Mushroom cloud">mushroom cloud</a> reached 7.5 miles (12.1&#160;km) in height. It was heard as far away as <a href="/wiki/El_Paso,_Texas" title="El Paso, Texas">El Paso, Texas</a>, so Groves issued a cover story about an ammunition magazine explosion at Alamogordo Field.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993372–374_218-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993372–374-218"><span class="cite-bracket">&#91;</span>218<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEJones1985514–517_217-1" class="reference"><a href="#cite_note-FOOTNOTEJones1985514–517-217"><span class="cite-bracket">&#91;</span>217<span class="cite-bracket">&#93;</span></a></sup> <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i><span class="nowrap" style="padding-left:0.1em;">&#39;</span> <a href="/wiki/William_L._Laurence" title="William L. Laurence">William L. Laurence</a>, who served as the Manhattan Project's press officer, helped put together the cover-story, including another press release in case of his own death. The media statement was issued by the <a href="/wiki/Second_Air_Force" title="Second Air Force">Second Air Force</a>. The media would later be invited to the site in September 1945 following the bombing of Hiroshima and Nagasaki.<sup id="cite_ref-219" class="reference"><a href="#cite_note-219"><span class="cite-bracket">&#91;</span>219<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Project_Alberta">Project Alberta</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=19" title="Edit section: Project Alberta"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Project_Alberta" title="Project Alberta">Project Alberta</a></div> <p>Project Alberta, also known as Project A, was formed in March 1945, absorbing existing groups of Parsons's O Division that were working on bomb preparation and delivery. These included Ramsey's O-2 (Delivery) Group, Birch's O-1 (Gun) Group, Bainbridge's X-2 (Development, Engineering, and Tests) Group, Brode's O-3 (Fuse Development) Group and George Galloway's O-4 (Engineering) Group.<sup id="cite_ref-FOOTNOTERamsey2012340_220-0" class="reference"><a href="#cite_note-FOOTNOTERamsey2012340-220"><span class="cite-bracket">&#91;</span>220<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-org_221-0" class="reference"><a href="#cite_note-org-221"><span class="cite-bracket">&#91;</span>221<span class="cite-bracket">&#93;</span></a></sup> Its role was to support the bomb delivery effort. Parsons became the head of Project Alberta, with Ramsey as his scientific and technical deputy, and Ashworth as his operations officer and military alternate.<sup id="cite_ref-FOOTNOTERamsey2012346_222-0" class="reference"><a href="#cite_note-FOOTNOTERamsey2012346-222"><span class="cite-bracket">&#91;</span>222<span class="cite-bracket">&#93;</span></a></sup> In all, Project Alberta consisted of 51 Army, Navy and civilian personnel.<sup id="cite_ref-FOOTNOTECampbell2005143_223-0" class="reference"><a href="#cite_note-FOOTNOTECampbell2005143-223"><span class="cite-bracket">&#91;</span>223<span class="cite-bracket">&#93;</span></a></sup> The 1st Technical Service Detachment, to which the personnel of Project Alberta were administratively assigned, was commanded by <a href="/wiki/Lieutenant_Colonel_(United_States)" class="mw-redirect" title="Lieutenant Colonel (United States)">Lieutenant Colonel</a> Peer de Silva,<sup id="cite_ref-FOOTNOTECampbell2005156_224-0" class="reference"><a href="#cite_note-FOOTNOTECampbell2005156-224"><span class="cite-bracket">&#91;</span>224<span class="cite-bracket">&#93;</span></a></sup> and provided security and housing services on Tinian.<sup id="cite_ref-FOOTNOTEHawkins1961286_225-0" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961286-225"><span class="cite-bracket">&#91;</span>225<span class="cite-bracket">&#93;</span></a></sup> There were two bomb assembly teams, a Fat Man Assembly Team under Commander Norris Bradbury and Roger Warner, and a Little Boy Assembly Team under Birch. <a href="/wiki/Philip_Morrison" title="Philip Morrison">Philip Morrison</a> was the head of the Pit Crew, <a href="/wiki/Bernard_Waldman" title="Bernard Waldman">Bernard Waldman</a> and <a href="/wiki/Luis_W._Alvarez" class="mw-redirect" title="Luis W. Alvarez">Luis Alvarez</a> led the Aerial Observation Team,<sup id="cite_ref-FOOTNOTERamsey2012346_222-1" class="reference"><a href="#cite_note-FOOTNOTERamsey2012346-222"><span class="cite-bracket">&#91;</span>222<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-org_221-1" class="reference"><a href="#cite_note-org-221"><span class="cite-bracket">&#91;</span>221<span class="cite-bracket">&#93;</span></a></sup> and Sheldon Dike was in charge of the Aircraft Ordnance Team.<sup id="cite_ref-FOOTNOTEHawkins1961286_225-1" class="reference"><a href="#cite_note-FOOTNOTEHawkins1961286-225"><span class="cite-bracket">&#91;</span>225<span class="cite-bracket">&#93;</span></a></sup> Physicists Robert Serber and <a href="/wiki/William_Penney" class="mw-redirect" title="William Penney">William Penney</a>, and US Army <a href="/wiki/Captain_(United_States_O-3)" title="Captain (United States O-3)">Captain</a> James F. Nolan, a medical expert, were special consultants.<sup id="cite_ref-FOOTNOTECampbell2005157_226-0" class="reference"><a href="#cite_note-FOOTNOTECampbell2005157-226"><span class="cite-bracket">&#91;</span>226<span class="cite-bracket">&#93;</span></a></sup> All members of Project Alberta had volunteered for the mission.<sup id="cite_ref-FOOTNOTERuss199030_227-0" class="reference"><a href="#cite_note-FOOTNOTERuss199030-227"><span class="cite-bracket">&#91;</span>227<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/19/Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg/220px-Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg" decoding="async" width="220" height="175" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/19/Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg/330px-Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/19/Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg/440px-Deak_Parsons_supervises_loading_of_Little_Boy_into_Enola_Gay.jpg 2x" data-file-width="900" data-file-height="714" /></a><figcaption><a href="/wiki/Deak_Parsons" class="mw-redirect" title="Deak Parsons">Deak Parsons</a> (right) supervises loading the Little Boy bomb into the B-29 <i><a href="/wiki/Enola_Gay" title="Enola Gay">Enola Gay</a></i>. <a href="/wiki/Norman_Ramsey" class="mw-redirect" title="Norman Ramsey">Norman Ramsey</a> is on his left, with his back to the camera.</figcaption></figure> <p>Project Alberta proceeded with the plan to have the Little Boy ready by 1 August, and the first Fat Man ready for use as soon as possible after that.<sup id="cite_ref-FOOTNOTERuss199052_228-0" class="reference"><a href="#cite_note-FOOTNOTERuss199052-228"><span class="cite-bracket">&#91;</span>228<span class="cite-bracket">&#93;</span></a></sup> In the meantime, a series of twelve combat missions were flown between 20 and 29 July against targets in Japan using high-explosive <a href="/wiki/Pumpkin_bomb" title="Pumpkin bomb">pumpkin bombs</a>, versions of the Fat Man with the explosives, but not the fissile core.<sup id="cite_ref-FOOTNOTECampbell200527_229-0" class="reference"><a href="#cite_note-FOOTNOTECampbell200527-229"><span class="cite-bracket">&#91;</span>229<span class="cite-bracket">&#93;</span></a></sup> Project Alberta's Sheldon Dike and Milo Bolstead flew on some of these missions, as did the British observer <a href="/wiki/Group_Captain" class="mw-redirect" title="Group Captain">Group Captain</a> <a href="/wiki/Leonard_Cheshire" title="Leonard Cheshire">Leonard Cheshire</a>.<sup id="cite_ref-FOOTNOTECampbell200550_230-0" class="reference"><a href="#cite_note-FOOTNOTECampbell200550-230"><span class="cite-bracket">&#91;</span>230<span class="cite-bracket">&#93;</span></a></sup> Four Little Boy pre-assemblies, L-1, L-2, L-5 and L-6 were expended in test drops.<sup id="cite_ref-FOOTNOTECampbell200546,_80_231-0" class="reference"><a href="#cite_note-FOOTNOTECampbell200546,_80-231"><span class="cite-bracket">&#91;</span>231<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTECoster-Mullen2012100–101_232-0" class="reference"><a href="#cite_note-FOOTNOTECoster-Mullen2012100–101-232"><span class="cite-bracket">&#91;</span>232<span class="cite-bracket">&#93;</span></a></sup> The Little Boy team had the live bomb completely assembled and ready for use on 31 July.<sup id="cite_ref-FOOTNOTERuss199055_233-0" class="reference"><a href="#cite_note-FOOTNOTERuss199055-233"><span class="cite-bracket">&#91;</span>233<span class="cite-bracket">&#93;</span></a></sup> The final item of preparation for the operation came on 29 July 1945. Orders for the attack were issued to <a href="/wiki/General_(United_States)" title="General (United States)">General</a> <a href="/wiki/Carl_Spaatz" title="Carl Spaatz">Carl Spaatz</a> on 25 July under the signature of General <a href="/wiki/Thomas_T._Handy" title="Thomas T. Handy">Thomas T. Handy</a>, the acting <a href="/wiki/Chief_of_Staff_of_the_United_States_Army" title="Chief of Staff of the United States Army">Chief of Staff of the United States Army</a>, since <a href="/wiki/General_of_the_Army" class="mw-redirect" title="General of the Army">General of the Army</a> <a href="/wiki/George_C._Marshall" title="George C. Marshall">George C. Marshall</a> was at the <a href="/wiki/Potsdam_Conference" title="Potsdam Conference">Potsdam Conference</a> with <a href="/wiki/President_of_the_United_States" title="President of the United States">President</a> <a href="/wiki/Harry_S._Truman" title="Harry S. Truman">Harry S. Truman</a>.<sup id="cite_ref-FOOTNOTERhodes1986691_234-0" class="reference"><a href="#cite_note-FOOTNOTERhodes1986691-234"><span class="cite-bracket">&#91;</span>234<span class="cite-bracket">&#93;</span></a></sup> The order designated four targets: <a href="/wiki/Hiroshima" title="Hiroshima">Hiroshima</a>, <a href="/wiki/Kokura" title="Kokura">Kokura</a>, <a href="/wiki/Niigata,_Niigata" class="mw-redirect" title="Niigata, Niigata">Niigata</a>, and <a href="/wiki/Nagasaki" title="Nagasaki">Nagasaki</a>, and ordered the attack to be made "as soon as weather will permit after about 3 August".<sup id="cite_ref-FOOTNOTECampbell200541_235-0" class="reference"><a href="#cite_note-FOOTNOTECampbell200541-235"><span class="cite-bracket">&#91;</span>235<span class="cite-bracket">&#93;</span></a></sup> </p><p>Assembly of a Fat Man unit was a complex operation involving personnel from the High Explosive, Pit, Fusing and Firing teams. To prevent the assembly building from becoming overcrowded and thereby causing an accident, Parsons limited the numbers allowed inside at any time. Personnel waiting to perform a specific task had to wait their turn outside the building. The first Fat Man pre-assembly, known as F13, was assembled by 31 July, and expended in a drop test the next day. This was followed by F18 on 4 August, which was dropped the next day.<sup id="cite_ref-FOOTNOTERuss199056–57_236-0" class="reference"><a href="#cite_note-FOOTNOTERuss199056–57-236"><span class="cite-bracket">&#91;</span>236<span class="cite-bracket">&#93;</span></a></sup> Three sets of Fat Man pre-assemblies, designated F31, F32, and F33, arrived on B-29s of the <a href="/wiki/509th_Composite_Group" title="509th Composite Group">509th Composite Group</a> and <a href="/wiki/216th_Army_Air_Forces_Base_Unit" title="216th Army Air Forces Base Unit">216th Army Air Forces Base Unit</a> on 2 August. On inspection, the high explosive blocks of F32 were found to be badly cracked and unserviceable. The other two were assembled, with F33 earmarked for a rehearsal and F31 for operational use.<sup id="cite_ref-FOOTNOTECampbell200538–40_237-0" class="reference"><a href="#cite_note-FOOTNOTECampbell200538–40-237"><span class="cite-bracket">&#91;</span>237<span class="cite-bracket">&#93;</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Fat_Man_on_Tinian_77-BT-186.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Fat_Man_on_Tinian_77-BT-186.jpg/220px-Fat_Man_on_Tinian_77-BT-186.jpg" decoding="async" width="220" height="173" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Fat_Man_on_Tinian_77-BT-186.jpg/330px-Fat_Man_on_Tinian_77-BT-186.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Fat_Man_on_Tinian_77-BT-186.jpg/440px-Fat_Man_on_Tinian_77-BT-186.jpg 2x" data-file-width="900" data-file-height="709" /></a><figcaption>Fat Man bomb, with liquid asphalt sealant sprayed on the casing's seams, is readied on Tinian.</figcaption></figure> <p>Parsons, as the weaponeer, was in command of the Hiroshima mission. With <a href="/wiki/Second_Lieutenant" class="mw-redirect" title="Second Lieutenant">Second Lieutenant</a> <a href="/wiki/Morris_R._Jeppson" title="Morris R. Jeppson">Morris R. Jeppson</a> of the 1st Ordnance Squadron, he inserted the Little Boy's powder bags in the <i><a href="/wiki/Enola_Gay" title="Enola Gay">Enola Gay</a></i><span class="nowrap" style="padding-left:0.1em;">&#39;</span>s bomb bay in flight. Before climbing to altitude on approach to the target, Jeppson switched the three safety plugs between the electrical connectors of the internal battery and the firing mechanism from green to red. The bomb was then fully armed. Jeppson monitored its circuits.<sup id="cite_ref-FOOTNOTECoster-Mullen201234–35_238-0" class="reference"><a href="#cite_note-FOOTNOTECoster-Mullen201234–35-238"><span class="cite-bracket">&#91;</span>238<span class="cite-bracket">&#93;</span></a></sup> Four other members of Project Alberta flew on the Hiroshima mission. <a href="/wiki/Luis_Walter_Alvarez" title="Luis Walter Alvarez">Luis Alvarez</a>, <a href="/wiki/Harold_Agnew" title="Harold Agnew">Harold Agnew</a> and <a href="/wiki/Lawrence_H._Johnston" title="Lawrence H. Johnston">Lawrence H. Johnston</a> were on the instrument plane <i><a href="/wiki/The_Great_Artiste_(B-29)" class="mw-redirect" title="The Great Artiste (B-29)">The Great Artiste</a></i>. They dropped "Bangometer" canisters to measure the force of the blast, but this was not used to calculate the yield at the time.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993393_239-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993393-239"><span class="cite-bracket">&#91;</span>239<span class="cite-bracket">&#93;</span></a></sup> Bernard Waldman was the camera operator on the <a href="/wiki/Necessary_Evil_(aircraft)" title="Necessary Evil (aircraft)">observation aircraft</a>. He was equipped with a special high-speed Fastax movie camera with six seconds of film in order to record the blast. Waldman forgot to open the camera shutter, and no film was exposed.<sup id="cite_ref-240" class="reference"><a href="#cite_note-240"><span class="cite-bracket">&#91;</span>240<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEAlvarezTrower198766_241-0" class="reference"><a href="#cite_note-FOOTNOTEAlvarezTrower198766-241"><span class="cite-bracket">&#91;</span>241<span class="cite-bracket">&#93;</span></a></sup> Other members of the team flew to <a href="/wiki/Iwo_Jima" title="Iwo Jima">Iwo Jima</a> in case <i>Enola Gay</i> was forced to land there, but this was not required.<sup id="cite_ref-FOOTNOTERuss199060_242-0" class="reference"><a href="#cite_note-FOOTNOTERuss199060-242"><span class="cite-bracket">&#91;</span>242<span class="cite-bracket">&#93;</span></a></sup> </p><p>Purnell, Parsons, <a href="/wiki/Paul_Tibbets" title="Paul Tibbets">Paul Tibbets</a>, Spaatz and <a href="/wiki/Curtis_LeMay" title="Curtis LeMay">Curtis LeMay</a> met on Guam on 7 August, the day after the Hiroshima attack, to discuss what should be done next. Parsons said that Project Alberta would have a Fat Man bomb ready by 11 August, as originally planned, but Tibbets pointed to weather reports indicating poor flying conditions on that day due to a storm, and asked if it could be readied by 9 August. Parsons agreed to do so.<sup id="cite_ref-FOOTNOTERuss199064–65_243-0" class="reference"><a href="#cite_note-FOOTNOTERuss199064–65-243"><span class="cite-bracket">&#91;</span>243<span class="cite-bracket">&#93;</span></a></sup> For this mission, Ashworth was the weaponeer, with <a href="/wiki/Lieutenant_(navy)" title="Lieutenant (navy)">Lieutenant</a> Philip M. Barnes, of the 1st Ordnance Squadron as assistant weaponeer on the B-29 <i><a href="/wiki/Bockscar" title="Bockscar">Bockscar</a></i>. Walter Goodman and Lawrence H. Johnston were on board the instrumentation aircraft, <i>The Great Artiste</i>. Leonard Cheshire and William Penney were on the observation plane <i><a href="/wiki/Big_Stink_(B-29)" class="mw-redirect" title="Big Stink (B-29)">Big Stink</a></i>.<sup id="cite_ref-eyewitness_244-0" class="reference"><a href="#cite_note-eyewitness-244"><span class="cite-bracket">&#91;</span>244<span class="cite-bracket">&#93;</span></a></sup> Robert Serber was supposed to be on board but was left behind by the aircraft commander because he had forgotten his parachute.<sup id="cite_ref-remembered_245-0" class="reference"><a href="#cite_note-remembered-245"><span class="cite-bracket">&#91;</span>245<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Health_and_safety">Health and safety</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=20" title="Edit section: Health and safety"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg" class="mw-file-description"><img alt="A shack surrounded by pine trees. There is snow on the ground. A man and a woman in white lab coats are pulling on a rope, which is attached to a small trolley on a wooden platform. On top of the trolley is a large cylindrical object." src="//upload.wikimedia.org/wikipedia/commons/thumb/8/80/Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg/220px-Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg" decoding="async" width="220" height="168" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/80/Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg/330px-Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/80/Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg/440px-Remote_handling_of_a_kilocurie_source_of_radiolanthanum.jpg 2x" data-file-width="2702" data-file-height="2064" /></a><figcaption>Remote handling of a kilocurie source of radiolanthanum for a <a href="/wiki/RaLa_Experiment" title="RaLa Experiment">RaLa Experiment</a> at Los Alamos</figcaption></figure> <p>A medical program was established at Los Alamos under Captain James F. Nolan of the <a href="/wiki/United_States_Army_Medical_Corps" title="United States Army Medical Corps">United States Army Medical Corps</a>.<sup id="cite_ref-FOOTNOTEWarren1966879_246-0" class="reference"><a href="#cite_note-FOOTNOTEWarren1966879-246"><span class="cite-bracket">&#91;</span>246<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-247" class="reference"><a href="#cite_note-247"><span class="cite-bracket">&#91;</span>247<span class="cite-bracket">&#93;</span></a></sup> Initially, a small five-bed infirmary was established for civilians, and a three-bed infirmary for military personnel. More serious cases were handled by the Army's Bruns General Hospital in Santa Fe, but this was soon regarded as unsatisfactory due to the loss of time due to the long trip, and security risks. Nolan recommended that the infirmaries be consolidated and expanded into a 60-bed hospital. A 54-bed hospital was opened in 1944, staffed by Army personnel. A dentist arrived in March 1944.<sup id="cite_ref-FOOTNOTEJones1985424–426_248-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985424–426-248"><span class="cite-bracket">&#91;</span>248<span class="cite-bracket">&#93;</span></a></sup> A <a href="/wiki/United_States_Army_Veterinary_Corps" title="United States Army Veterinary Corps">Veterinary Corps</a> officer, Captain J. Stevenson, had already been assigned to look after the guard dogs.<sup id="cite_ref-FOOTNOTEWarren1966879_246-1" class="reference"><a href="#cite_note-FOOTNOTEWarren1966879-246"><span class="cite-bracket">&#91;</span>246<span class="cite-bracket">&#93;</span></a></sup> </p><p>Laboratory facilities for medical research were limited, but some research was conducted into the effects of radiation, and the absorption and toxic effects of metals, particularly plutonium and beryllium, mainly as a result of accidents.<sup id="cite_ref-FOOTNOTEWarren1966881_249-0" class="reference"><a href="#cite_note-FOOTNOTEWarren1966881-249"><span class="cite-bracket">&#91;</span>249<span class="cite-bracket">&#93;</span></a></sup> The Health Group began conducting urine tests of laboratory workers in early 1945, and many of these revealed dangerous levels of plutonium.<sup id="cite_ref-FOOTNOTEHacker198768–69_250-0" class="reference"><a href="#cite_note-FOOTNOTEHacker198768–69-250"><span class="cite-bracket">&#91;</span>250<span class="cite-bracket">&#93;</span></a></sup> Work on the Water Boiler also occasionally exposed workers to dangerous fission products.<sup id="cite_ref-FOOTNOTEHacker198771_251-0" class="reference"><a href="#cite_note-FOOTNOTEHacker198771-251"><span class="cite-bracket">&#91;</span>251<span class="cite-bracket">&#93;</span></a></sup> There were 24 fatal accidents at Los Alamos between its opening in 1943 and September 1946. Most involved construction workers. Four scientists died, including <a href="/wiki/Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a> and <a href="/wiki/Louis_Slotin" title="Louis Slotin">Louis Slotin</a> in <a href="/wiki/Criticality_accident" title="Criticality accident">criticality accidents</a> involving the <a href="/wiki/Demon_core" title="Demon core">demon core</a>.<sup id="cite_ref-252" class="reference"><a href="#cite_note-252"><span class="cite-bracket">&#91;</span>252<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Security">Security</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=21" title="Edit section: Security"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Atomic_spies" title="Atomic spies">Atomic spies</a></div> <p>On 10 March 1945, a Japanese <a href="/wiki/Fire_balloon" class="mw-redirect" title="Fire balloon">fire balloon</a> struck a power line, and the resulting power surge caused the Manhattan Project's reactors at the Hanford site to be temporarily shut down.<sup id="cite_ref-FOOTNOTEJones1985267_253-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985267-253"><span class="cite-bracket">&#91;</span>253<span class="cite-bracket">&#93;</span></a></sup> This generated great concern at Los Alamos that the site might come under attack. One night found everyone staring at a strange light in the sky. Oppenheimer later recalled this demonstrated that "even a group of scientists is not proof against the errors of suggestion and hysteria".<sup id="cite_ref-FOOTNOTEConant2005253_254-0" class="reference"><a href="#cite_note-FOOTNOTEConant2005253-254"><span class="cite-bracket">&#91;</span>254<span class="cite-bracket">&#93;</span></a></sup> </p><p>With so many people involved, security was a difficult task. A special <a href="/wiki/Counter_Intelligence_Corps" class="mw-redirect" title="Counter Intelligence Corps">Counter Intelligence Corps</a> detachment was formed to handle the Manhattan Project's security issues.<sup id="cite_ref-FOOTNOTEJones1985258–260_255-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985258–260-255"><span class="cite-bracket">&#91;</span>255<span class="cite-bracket">&#93;</span></a></sup> By 1943, it was clear that the Soviet Union was attempting to penetrate the project.<sup id="cite_ref-FOOTNOTEJones1985261–265_256-0" class="reference"><a href="#cite_note-FOOTNOTEJones1985261–265-256"><span class="cite-bracket">&#91;</span>256<span class="cite-bracket">&#93;</span></a></sup> The most successful Soviet spy was <a href="/wiki/Klaus_Fuchs" title="Klaus Fuchs">Klaus Fuchs</a> of the British Mission.<sup id="cite_ref-FOOTNOTEGroves1962142–145_257-0" class="reference"><a href="#cite_note-FOOTNOTEGroves1962142–145-257"><span class="cite-bracket">&#91;</span>257<span class="cite-bracket">&#93;</span></a></sup> The 1950 revelation of his espionage activities damaged the United States' nuclear cooperation with Britain and Canada.<sup id="cite_ref-FOOTNOTEHewlettDuncan1969312–314_258-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettDuncan1969312–314-258"><span class="cite-bracket">&#91;</span>258<span class="cite-bracket">&#93;</span></a></sup> Subsequently, other instances of espionage were uncovered, leading to the arrest of <a href="/wiki/Harry_Gold" title="Harry Gold">Harry Gold</a>, <a href="/wiki/David_Greenglass" title="David Greenglass">David Greenglass</a> and <a href="/wiki/Ethel_and_Julius_Rosenberg" class="mw-redirect" title="Ethel and Julius Rosenberg">Ethel and Julius Rosenberg</a>.<sup id="cite_ref-FOOTNOTEHewlettDuncan1969472_259-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettDuncan1969472-259"><span class="cite-bracket">&#91;</span>259<span class="cite-bracket">&#93;</span></a></sup> Other spies like <a href="/wiki/Theodore_Hall" title="Theodore Hall">Theodore Hall</a> remained unknown for decades.<sup id="cite_ref-260" class="reference"><a href="#cite_note-260"><span class="cite-bracket">&#91;</span>260<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Post-war">Post-war</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=22" title="Edit section: Post-war"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Bradbury_Groves_Jette_etc._681002.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Bradbury_Groves_Jette_etc._681002.jpg/220px-Bradbury_Groves_Jette_etc._681002.jpg" decoding="async" width="220" height="175" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Bradbury_Groves_Jette_etc._681002.jpg/330px-Bradbury_Groves_Jette_etc._681002.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Bradbury_Groves_Jette_etc._681002.jpg/440px-Bradbury_Groves_Jette_etc._681002.jpg 2x" data-file-width="1200" data-file-height="953" /></a><figcaption>Bradbury (left) examines plans for new laboratory sites and permanent housing with Leslie Groves of the <a href="/wiki/Armed_Forces_Special_Weapons_Project" title="Armed Forces Special Weapons Project">Armed Forces Special Weapons Project</a> (center) and Eric Jette (right) in April 1947; Colonel Lyle E. Seeman stands behind Bradbury, second from the left.</figcaption></figure> <p>After the war ended on 14 August 1945, Oppenheimer informed Groves of his intention to resign as director of the Los Alamos Laboratory, but agreed to remain until a suitable replacement could be found. Groves wanted someone with both a solid academic background and a high standing within the project. Oppenheimer recommended Norris Bradbury. This was agreeable to Groves, who liked the fact that as a naval officer Bradbury was both a military man and a scientist. Bradbury accepted the offer on a six-month trial basis. Groves announced this at a meeting of division leaders on 18 September.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993625–626_261-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993625–626-261"><span class="cite-bracket">&#91;</span>261<span class="cite-bracket">&#93;</span></a></sup> Parsons arranged for Bradbury to be quickly discharged from the Navy,<sup id="cite_ref-FOOTNOTEEbinger200682–83_262-0" class="reference"><a href="#cite_note-FOOTNOTEEbinger200682–83-262"><span class="cite-bracket">&#91;</span>262<span class="cite-bracket">&#93;</span></a></sup> which awarded him the <a href="/wiki/Legion_of_Merit" title="Legion of Merit">Legion of Merit</a> for his wartime services.<sup id="cite_ref-FOOTNOTEAgnewSchreiber19989_263-0" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19989-263"><span class="cite-bracket">&#91;</span>263<span class="cite-bracket">&#93;</span></a></sup> He remained in the Naval Reserve, though, ultimately retiring in 1961 with the rank of captain.<sup id="cite_ref-FOOTNOTEEbinger200698_264-0" class="reference"><a href="#cite_note-FOOTNOTEEbinger200698-264"><span class="cite-bracket">&#91;</span>264<span class="cite-bracket">&#93;</span></a></sup> On 16 October 1945, there was a ceremony at Los Alamos at which Groves presented the laboratory with the <a href="/wiki/Army-Navy_%22E%22_Award" title="Army-Navy &quot;E&quot; Award">Army-Navy "E" Award</a>, and presented Oppenheimer with a certificate of appreciation. Bradbury became the laboratory's second director the following day.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402_265-0" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402-265"><span class="cite-bracket">&#91;</span>265<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-FOOTNOTEAgnewSchreiber19984_266-0" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19984-266"><span class="cite-bracket">&#91;</span>266<span class="cite-bracket">&#93;</span></a></sup> </p><p>The first months of Bradbury's directorship were particularly trying. He had hoped that Atomic Energy Act of 1946 would be quickly passed by Congress and the wartime Manhattan Project would be superseded by a new, permanent organization. It soon became clear that this would take more than six months. President Harry S. Truman did not sign the act creating the <a href="/wiki/United_States_Atomic_Energy_Commission" title="United States Atomic Energy Commission">Atomic Energy Commission</a> into law until 1 August 1946, and it did not become active until 1 January 1947. In the meantime, Groves' legal authority to act was limited.<sup id="cite_ref-FOOTNOTEAgnewSchreiber19985_267-0" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19985-267"><span class="cite-bracket">&#91;</span>267<span class="cite-bracket">&#93;</span></a></sup> </p><p>Most of the scientists at Los Alamos were eager to return to their laboratories and universities, and by February 1946 all of the wartime division heads had left, but a talented core remained. Darol Froman became head of Robert Bacher's G division, now renamed M Division. Eric Jette became responsible for Chemistry and Metallurgy, John H. Manley for Physics, <a href="/wiki/George_Placzek" title="George Placzek">George Placzek</a> for Theory, Max Roy for Explosives, and Roger Wagner for Ordnance.<sup id="cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402_265-1" class="reference"><a href="#cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402-265"><span class="cite-bracket">&#91;</span>265<span class="cite-bracket">&#93;</span></a></sup> Z Division was created in July 1945 to control testing, stock piling, and bomb assembly activities. It was named after <a href="/wiki/Jerrold_R._Zacharias" title="Jerrold R. Zacharias">Jerrold R. Zacharias</a>, its leader until 17 October 1945, when he returned to MIT, and was succeeded by Roger S. Warner. It moved to <a href="/wiki/Sandia_Base" title="Sandia Base">Sandia Base</a> between March and July 1946, except for its Z-4 (Mechanical Engineering) Group, which followed in February 1947.<sup id="cite_ref-FOOTNOTETruslowSmith196195–96_268-0" class="reference"><a href="#cite_note-FOOTNOTETruslowSmith196195–96-268"><span class="cite-bracket">&#91;</span>268<span class="cite-bracket">&#93;</span></a></sup> </p><p>The number of personnel at the Los Alamos Laboratory plummeted from its wartime peak of over 3,000 to around 1,000, but many were still living in substandard temporary wartime accommodation.<sup id="cite_ref-FOOTNOTEAgnewSchreiber19985_267-1" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19985-267"><span class="cite-bracket">&#91;</span>267<span class="cite-bracket">&#93;</span></a></sup> Despite the reduced staff, Bradbury still had to provide support for <a href="/wiki/Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a>, the nuclear tests in the Pacific.<sup id="cite_ref-FOOTNOTEAgnewSchreiber19986_269-0" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19986-269"><span class="cite-bracket">&#91;</span>269<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Ralph_A._Sawyer" title="Ralph A. Sawyer">Ralph A. Sawyer</a> was appointed the Technical Director with Marshall Holloway from B Division and Roger Warner from Z Division as associate directors. Two ships were assigned for Los Alamos Laboratory personnel, the <a href="/wiki/USS_Cumberland_Sound" title="USS Cumberland Sound">USS&#160;<i>Cumberland Sound</i></a> and <a href="/wiki/USS_Albemarle_(AV-5)" title="USS Albemarle (AV-5)"><i>Albemarle</i></a>. Operation Crossroads cost the Los Alamos Laboratory over one million dollars, and the services of 150 personnel (about one-eighth of its staff) for nine months.<sup id="cite_ref-FOOTNOTETruslowSmith196122–23_270-0" class="reference"><a href="#cite_note-FOOTNOTETruslowSmith196122–23-270"><span class="cite-bracket">&#91;</span>270<span class="cite-bracket">&#93;</span></a></sup> As the United States had only about ten atomic bombs in mid-1946 about one fifth of the stockpile was expended.<sup id="cite_ref-271" class="reference"><a href="#cite_note-271"><span class="cite-bracket">&#91;</span>271<span class="cite-bracket">&#93;</span></a></sup> </p><p>The Los Alamos Laboratory became the <a href="/wiki/Los_Alamos_Scientific_Laboratory" class="mw-redirect" title="Los Alamos Scientific Laboratory">Los Alamos Scientific Laboratory</a> in January 1947.<sup id="cite_ref-FOOTNOTETruslowSmith1961v_272-0" class="reference"><a href="#cite_note-FOOTNOTETruslowSmith1961v-272"><span class="cite-bracket">&#91;</span>272<span class="cite-bracket">&#93;</span></a></sup> The contract with the University of California that had been negotiated in 1943 allowed the university to terminate it three months after the end of hostilities, and it served notice. There were concerns about the university operating a laboratory outside the state of California. The university was persuaded to rescind its notice,<sup id="cite_ref-FOOTNOTEEbinger200689–90_273-0" class="reference"><a href="#cite_note-FOOTNOTEEbinger200689–90-273"><span class="cite-bracket">&#91;</span>273<span class="cite-bracket">&#93;</span></a></sup> and the operating contract was extended until July 1948.<sup id="cite_ref-FOOTNOTEHewlettDuncan196943_274-0" class="reference"><a href="#cite_note-FOOTNOTEHewlettDuncan196943-274"><span class="cite-bracket">&#91;</span>274<span class="cite-bracket">&#93;</span></a></sup> Bradbury would remain director until 1970.<sup id="cite_ref-FOOTNOTEAgnewSchreiber19983_275-0" class="reference"><a href="#cite_note-FOOTNOTEAgnewSchreiber19983-275"><span class="cite-bracket">&#91;</span>275<span class="cite-bracket">&#93;</span></a></sup> The total cost of Project Y up to the end of 1946 was $57.88 million (equivalent to $900 million in 2023).<sup id="cite_ref-FOOTNOTEManhattan_District1947aS8_68-1" class="reference"><a href="#cite_note-FOOTNOTEManhattan_District1947aS8-68"><span class="cite-bracket">&#91;</span>68<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=23" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-nris-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-nris_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://npgallery.nps.gov/NRHP">"National Register Information System"</a>. <i><a href="/wiki/National_Register_of_Historic_Places" title="National Register of Historic Places">National Register of Historic Places</a></i>. <a href="/wiki/National_Park_Service" title="National Park Service">National Park Service</a>. 9 July 2010.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=National+Register+of+Historic+Places&amp;rft.atitle=National+Register+Information+System&amp;rft.date=2010-07-09&amp;rft_id=https%3A%2F%2Fnpgallery.nps.gov%2FNRHP&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTECompton195614-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECompton195614_2-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCompton1956">Compton 1956</a>, p.&#160;14.</span> </li> <li id="cite_note-FOOTNOTERhodes1986251–254-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986251–254_3-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, pp.&#160;251–254.</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHahnStrassmann1939" class="citation journal cs1"><a href="/wiki/Otto_Hahn" title="Otto Hahn">Hahn, O.</a>; <a href="/wiki/Fritz_Strassmann" title="Fritz Strassmann">Strassmann, F.</a> (1939). "Über den Nachweis und das Verhalten der bei der Bestrahlung des Urans mittels Neutronen entstehenden Erdalkalimetalle" &#91;On the detection and characteristics of the alkaline earth metals formed by irradiation of uranium with neutrons&#93;. <i>Die Naturwissenschaften</i>. <b>27</b> (1): 11–15. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1939NW.....27...11H">1939NW.....27...11H</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2FBF01488241">10.1007/BF01488241</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&#160;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:5920336">5920336</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Die+Naturwissenschaften&amp;rft.atitle=%C3%9Cber+den+Nachweis+und+das+Verhalten+der+bei+der+Bestrahlung+des+Urans+mittels+Neutronen+entstehenden+Erdalkalimetalle&amp;rft.volume=27&amp;rft.issue=1&amp;rft.pages=11-15&amp;rft.date=1939&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A5920336%23id-name%3DS2CID&amp;rft_id=info%3Adoi%2F10.1007%2FBF01488241&amp;rft_id=info%3Abibcode%2F1939NW.....27...11H&amp;rft.aulast=Hahn&amp;rft.aufirst=O.&amp;rft.au=Strassmann%2C+F.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTERhodes1986256–263-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986256–263_5-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, pp.&#160;256–263.</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMeitnerFrisch1939" class="citation journal cs1"><a href="/wiki/Lise_Meitner" title="Lise Meitner">Meitner, Lise</a>; <a href="/wiki/Otto_Frisch" class="mw-redirect" title="Otto Frisch">Frisch, O. R.</a> (1939). <a rel="nofollow" class="external text" href="http://www.nature.com/physics/looking-back/meitner/index.html">"Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction"</a>. <i><a href="/wiki/Nature_(journal)" title="Nature (journal)">Nature</a></i>. <b>143</b> (3615): 239–240. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1939Natur.143..239M">1939Natur.143..239M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1038%2F143239a0">10.1038/143239a0</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&#160;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:4113262">4113262</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190428141914/http://www.nature.com/physics/looking-back/meitner/index.html">Archived</a> from the original on 28 April 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">19 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Nature&amp;rft.atitle=Disintegration+of+Uranium+by+Neutrons%3A+a+New+Type+of+Nuclear+Reaction&amp;rft.volume=143&amp;rft.issue=3615&amp;rft.pages=239-240&amp;rft.date=1939&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A4113262%23id-name%3DS2CID&amp;rft_id=info%3Adoi%2F10.1038%2F143239a0&amp;rft_id=info%3Abibcode%2F1939Natur.143..239M&amp;rft.aulast=Meitner&amp;rft.aufirst=Lise&amp;rft.au=Frisch%2C+O.+R.&amp;rft_id=http%3A%2F%2Fwww.nature.com%2Fphysics%2Flooking-back%2Fmeitner%2Findex.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson196229-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson196229_7-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;29.</span> </li> <li id="cite_note-FOOTNOTEJones198512-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones198512_8-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;12.</span> </li> <li id="cite_note-FOOTNOTEGowing196439–43,_407-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGowing196439–43,_407_9-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGowing1964">Gowing 1964</a>, pp.&#160;39–43, 407.</span> </li> <li id="cite_note-FOOTNOTEGowing196443–45-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGowing196443–45_10-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGowing1964">Gowing 1964</a>, pp.&#160;43–45.</span> </li> <li id="cite_note-FOOTNOTEGowing196478-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGowing196478_11-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGowing1964">Gowing 1964</a>, p.&#160;78.</span> </li> <li id="cite_note-FOOTNOTEGowing1964107–109-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGowing1964107–109_12-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGowing1964">Gowing 1964</a>, pp.&#160;107–109.</span> </li> <li id="cite_note-FOOTNOTERhodes1986372-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986372_13-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, p.&#160;372.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson196243–44-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson196243–44_14-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;43–44.</span> </li> <li id="cite_note-Electromagnetic_separation-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-Electromagnetic_separation_15-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOliphantShireCrowther1934" class="citation journal cs1"><a href="/wiki/Mark_Oliphant" title="Mark Oliphant">Oliphant, M. L. E.</a>; Shire, E. S.; Crowther, B. M. (15 October 1934). <a rel="nofollow" class="external text" href="https://doi.org/10.1098%2Frspa.1934.0197">"Separation of the Isotopes of Lithium and Some Nuclear Transformations Observed with Them"</a>. <i><a href="/wiki/Proceedings_of_the_Royal_Society" title="Proceedings of the Royal Society">Proceedings of the Royal Society</a></i>. <b>146</b> (859): 922–929. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1934RSPSA.146..922O">1934RSPSA.146..922O</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1098%2Frspa.1934.0197">10.1098/rspa.1934.0197</a></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Proceedings+of+the+Royal+Society&amp;rft.atitle=Separation+of+the+Isotopes+of+Lithium+and+Some+Nuclear+Transformations+Observed+with+Them&amp;rft.volume=146&amp;rft.issue=859&amp;rft.pages=922-929&amp;rft.date=1934-10-15&amp;rft_id=info%3Adoi%2F10.1098%2Frspa.1934.0197&amp;rft_id=info%3Abibcode%2F1934RSPSA.146..922O&amp;rft.aulast=Oliphant&amp;rft.aufirst=M.+L.+E.&amp;rft.au=Shire%2C+E.+S.&amp;rft.au=Crowther%2C+B.+M.&amp;rft_id=https%3A%2F%2Fdoi.org%2F10.1098%252Frspa.1934.0197&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson196246–47-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson196246–47_16-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;46–47.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson196250–51-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson196250–51_17-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;50–51.</span> </li> <li id="cite_note-FOOTNOTECompton195686-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECompton195686_18-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCompton1956">Compton 1956</a>, p.&#160;86.</span> </li> <li id="cite_note-FOOTNOTEMonk2012312–315-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMonk2012312–315_19-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, pp.&#160;312–315.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962103-20"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHewlettAnderson1962103_20-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHewlettAnderson1962103_20-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;103.</span> </li> <li id="cite_note-FOOTNOTECompton1956125–127-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECompton1956125–127_21-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCompton1956">Compton 1956</a>, pp.&#160;125–127.</span> </li> <li id="cite_note-FOOTNOTEMonk2012315–316-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMonk2012315–316_22-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, pp.&#160;315–316.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199342–44-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199342–44_23-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;42–44.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson196233–35-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson196233–35_24-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;33–35.</span> </li> <li id="cite_note-FOOTNOTESerberRhodes199221-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESerberRhodes199221_25-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSerberRhodes1992">Serber &amp; Rhodes 1992</a>, p.&#160;21.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199354–56-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199354–56_26-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;54–56.</span> </li> <li id="cite_note-FOOTNOTERhodes1986417-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986417_27-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, p.&#160;417.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199344–45-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199344–45_28-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;44–45.</span> </li> <li id="cite_note-FOOTNOTEBethe199130-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBethe199130_29-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBethe1991">Bethe 1991</a>, p.&#160;30.</span> </li> <li id="cite_note-FOOTNOTERhodes1986419-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986419_30-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, p.&#160;419.</span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKonopinskiMarvinTeller1946" class="citation web cs1"><a href="/wiki/Emil_Konopinski" title="Emil Konopinski">Konopinski, E. J</a>; Marvin, C.; <a href="/wiki/Edward_Teller" title="Edward Teller">Teller, Edward</a> (1946). <a rel="nofollow" class="external text" href="https://fas.org/sgp/othergov/doe/lanl/docs1/00329010.pdf">"Ignition of the Atmosphere with Nuclear Bombs"</a> <span class="cs1-format">(PDF)</span>. Los Alamos National Laboratory. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20050418002607/https://fas.org/sgp/othergov/doe/lanl/docs1/00329010.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 18 April 2005<span class="reference-accessdate">. Retrieved <span class="nowrap">23 November</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Ignition+of+the+Atmosphere+with+Nuclear+Bombs&amp;rft.pub=Los+Alamos+National+Laboratory&amp;rft.date=1946&amp;rft.aulast=Konopinski&amp;rft.aufirst=E.+J&amp;rft.au=Marvin%2C+C.&amp;rft.au=Teller%2C+Edward&amp;rft_id=https%3A%2F%2Ffas.org%2Fsgp%2Fothergov%2Fdoe%2Flanl%2Fdocs1%2F00329010.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEMonk2012321-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMonk2012321_32-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, p.&#160;321.</span> </li> <li id="cite_note-FOOTNOTEMonk2012325-33"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEMonk2012325_33-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEMonk2012325_33-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, p.&#160;325.</span> </li> <li id="cite_note-FOOTNOTEJones198582–83-34"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones198582–83_34-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones198582–83_34-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;82–83.</span> </li> <li id="cite_note-FOOTNOTEJones198577-35"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones198577_35-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;77.</span> </li> <li id="cite_note-FOOTNOTEGroves196260–61-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGroves196260–61_36-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;60–61.</span> </li> <li id="cite_note-FOOTNOTENichols198773-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTENichols198773_37-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFNichols1987">Nichols 1987</a>, p.&#160;73.</span> </li> <li id="cite_note-FOOTNOTEJones198587-38"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones198587_38-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones198587_38-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;87.</span> </li> <li id="cite_note-FOOTNOTEGroves196261–63-39"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEGroves196261–63_39-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEGroves196261–63_39-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;61–63.</span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://vault.fbi.gov/Katherine%20Oppenheimer/Katherine%20Oppenheimer%20Part%201%20of%201">"FBI file: Katherine Oppenheimer"</a> <span class="cs1-format">(PDF)</span>. <a href="/wiki/Federal_Bureau_of_Investigation" title="Federal Bureau of Investigation">Federal Bureau of Investigation</a>. 23 May 1944. p.&#160;2. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130525101636/http://vault.fbi.gov/Katherine%20Oppenheimer/Katherine%20Oppenheimer%20Part%201%20of%201/">Archived</a> from the original on 25 May 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">16 December</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=FBI+file%3A+Katherine+Oppenheimer&amp;rft.pages=2&amp;rft.pub=Federal+Bureau+of+Investigation&amp;rft.date=1944-05-23&amp;rft_id=http%3A%2F%2Fvault.fbi.gov%2FKatherine%2520Oppenheimer%2FKatherine%2520Oppenheimer%2520Part%25201%2520of%25201&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEMonk2012234–236-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMonk2012234–236_41-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, pp.&#160;234–236.</span> </li> <li id="cite_note-42"><span class="mw-cite-backlink"><b><a href="#cite_ref-42">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation news cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20071121210619/http://www.time.com/time/magazine/article/0,9171,800436,00.html">"The Brothers"</a>. <i><a href="/wiki/Time_(magazine)" title="Time (magazine)">Time</a></i>. 27 June 1949. Archived from <a rel="nofollow" class="external text" href="http://www.time.com/time/magazine/article/0,9171,800436,00.html">the original</a> on 21 November 2007<span class="reference-accessdate">. Retrieved <span class="nowrap">22 May</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Time&amp;rft.atitle=The+Brothers&amp;rft.date=1949-06-27&amp;rft_id=http%3A%2F%2Fwww.time.com%2Ftime%2Fmagazine%2Farticle%2F0%2C9171%2C800436%2C00.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEJones198583–84-43"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones198583–84_43-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones198583–84_43-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones198583–84_43-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;83–84.</span> </li> <li id="cite_note-FOOTNOTEGroves196264–65-44"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGroves196264–65_44-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;64–65.</span> </li> <li id="cite_note-FOOTNOTETruslow19732-45"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslow19732_45-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslow1973">Truslow 1973</a>, p.&#160;2.</span> </li> <li id="cite_note-FOOTNOTEFineRemington1972664–665-46"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEFineRemington1972664–665_46-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFFineRemington1972">Fine &amp; Remington 1972</a>, pp.&#160;664–665.</span> </li> <li id="cite_note-47"><span class="mw-cite-backlink"><b><a href="#cite_ref-47">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110420213027/http://www.lanl.gov/history/road/school-arsenal.shtml">"50th Anniversary Article: Oppenheimer's Better Idea: Ranch School Becomes Arsenal of Democracy"</a>. Los Alamos National Laboratory. Archived from <a rel="nofollow" class="external text" href="http://www.lanl.gov/history/road/school-arsenal.shtml">the original</a> on 20 April 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">6 April</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=50th+Anniversary+Article%3A+Oppenheimer%27s+Better+Idea%3A+Ranch+School+Becomes+Arsenal+of+Democracy&amp;rft.pub=Los+Alamos+National+Laboratory&amp;rft_id=http%3A%2F%2Fwww.lanl.gov%2Fhistory%2Froad%2Fschool-arsenal.shtml&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEGroves196266–67-48"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGroves196266–67_48-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;66–67.</span> </li> <li id="cite_note-FOOTNOTEJones1985328–331-49"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones1985328–331_49-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones1985328–331_49-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;328–331.</span> </li> <li id="cite_note-50"><span class="mw-cite-backlink"><b><a href="#cite_ref-50">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110420213401/http://www.lanl.gov/history/road/pdf/4-8-43.pdf">"Secretary of Agriculture granting use of land for Demolition Range"</a> <span class="cs1-format">(PDF)</span>. Los Alamos National Laboratory. 8 April 1943. Archived from <a rel="nofollow" class="external text" href="http://www.lanl.gov/history/road/pdf/4-8-43.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 20 April 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">6 April</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Secretary+of+Agriculture+granting+use+of+land+for+Demolition+Range&amp;rft.pub=Los+Alamos+National+Laboratory&amp;rft.date=1943-04-08&amp;rft_id=http%3A%2F%2Fwww.lanl.gov%2Fhistory%2Froad%2Fpdf%2F4-8-43.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a3.6-51"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a3.6_51-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;3.6.</span> </li> <li id="cite_note-52"><span class="mw-cite-backlink"><b><a href="#cite_ref-52">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFYardley2001" class="citation news cs1">Yardley, Jim (27 August 2001). <a rel="nofollow" class="external text" href="https://www.nytimes.com/2001/08/27/national/27LAND.html">"Land for Los Alamos Lab Taken Unfairly, Heirs Say"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200314190340/https://www.nytimes.com/2001/08/27/us/land-for-los-alamos-lab-taken-unfairly-heirs-say.html">Archived</a> from the original on 14 March 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">25 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=The+New+York+Times&amp;rft.atitle=Land+for+Los+Alamos+Lab+Taken+Unfairly%2C+Heirs+Say&amp;rft.date=2001-08-27&amp;rft.aulast=Yardley&amp;rft.aufirst=Jim&amp;rft_id=https%3A%2F%2Fwww.nytimes.com%2F2001%2F08%2F27%2Fnational%2F27LAND.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS3-53"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947aS3_53-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947aS3_53-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947aS3_53-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947aS3_53-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;S3.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a3.3-54"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a3.3_54-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;3.3.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a2.7-55"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a2.7_55-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;2.7.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947as4-56"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947as4_56-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;s4.</span> </li> <li id="cite_note-FOOTNOTEHunner200431–32-57"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHunner200431–32_57-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHunner200431–32_57-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHunner200431–32_57-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHunner200431–32_57-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, pp.&#160;31–32.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS5–S6-58"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947aS5–S6_58-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;S5–S6.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS19-59"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947aS19_59-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;S19.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a7.15-60"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a7.15_60-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;7.15.</span> </li> <li id="cite_note-FOOTNOTEHunner200440–41-61"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner200440–41_61-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, pp.&#160;40–41.</span> </li> <li id="cite_note-FOOTNOTEMonk2012339-62"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEMonk2012339_62-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFMonk2012">Monk 2012</a>, p.&#160;339.</span> </li> <li id="cite_note-FOOTNOTEHunner2004193-63"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner2004193_63-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, p.&#160;193.</span> </li> <li id="cite_note-FOOTNOTEChristman1998118-64"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEChristman1998118_64-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFChristman1998">Christman 1998</a>, p.&#160;118.</span> </li> <li id="cite_note-FOOTNOTEJones1985469-65"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985469_65-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;469.</span> </li> <li id="cite_note-FOOTNOTENichols198759,_175-66"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTENichols198759,_175_66-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFNichols1987">Nichols 1987</a>, pp.&#160;59, 175.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS9-67"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947aS9_67-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;S9.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS8-68"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947aS8_68-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947aS8_68-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;S8.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS16-69"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947aS16_69-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, p.&#160;S16.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a6.65–6.66-70"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a6.65–6.66_70-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;6.65–6.66.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947aS6–S8-71"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947aS6–S8_71-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947aS6–S8_71-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;S6–S8.</span> </li> <li id="cite_note-FOOTNOTEHunner200492–94-72"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner200492–94_72-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, pp.&#160;92–94.</span> </li> <li id="cite_note-FOOTNOTEHunner200429-73"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner200429_73-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, p.&#160;29.</span> </li> <li id="cite_note-FOOTNOTEJones1985474–475-74"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985474–475_74-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;474–475.</span> </li> <li id="cite_note-FOOTNOTEChambers19994–7-75"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEChambers19994–7_75-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFChambers1999">Chambers 1999</a>, pp.&#160;4–7.</span> </li> <li id="cite_note-FOOTNOTEChambers199941–49-76"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEChambers199941–49_76-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFChambers1999">Chambers 1999</a>, pp.&#160;41–49.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962230–232-77"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962230–232_77-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;230–232.</span> </li> <li id="cite_note-FOOTNOTEHawkins19615-78"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins19615_78-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins19615_78-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;5.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a7.1–7.2-79"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.1–7.2_79-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;7.1–7.2.</span> </li> <li id="cite_note-FOOTNOTEJones198586-80"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones198586_80-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones198586_80-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;86.</span> </li> <li id="cite_note-FOOTNOTEHunner200416-81"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner200416_81-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, p.&#160;16.</span> </li> <li id="cite_note-FOOTNOTEHunner200450-82"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHunner200450_82-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHunner2004">Hunner 2004</a>, p.&#160;50.</span> </li> <li id="cite_note-FOOTNOTEGroves1962153–154-83"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEGroves1962153–154_83-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEGroves1962153–154_83-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;153–154.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a6.33–6.34-84"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEManhattan_District1947a6.33–6.34_84-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;6.33–6.34.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a7.2–7.5-85"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a7.2–7.5_85-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;7.2–7.5.</span> </li> <li id="cite_note-FOOTNOTEHawkins196143-86"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196143_86-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;43.</span> </li> <li id="cite_note-FOOTNOTEHawkins19615–6-87"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins19615–6_87-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins19615–6_87-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;5–6.</span> </li> <li id="cite_note-FOOTNOTEConant200523-88"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEConant200523_88-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFConant2005">Conant 2005</a>, p.&#160;23.</span> </li> <li id="cite_note-FOOTNOTEGroves1962153-89"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGroves1962153_89-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, p.&#160;153.</span> </li> <li id="cite_note-FOOTNOTEManhattan_District1947a5.23–5.24-90"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEManhattan_District1947a5.23–5.24_90-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEManhattan_District1947a5.23–5.24_90-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFManhattan_District1947a">Manhattan District 1947a</a>, pp.&#160;5.23–5.24.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993109-91"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993109_91-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;109.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100-92"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100_92-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199399–100_92-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;99–100.</span> </li> <li id="cite_note-FOOTNOTEHowesHerzenberg199943–45-93"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHowesHerzenberg199943–45_93-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHowesHerzenberg1999">Howes &amp; Herzenberg 1999</a>, pp.&#160;43–45.</span> </li> <li id="cite_note-94"><span class="mw-cite-backlink"><b><a href="#cite_ref-94">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation news cs1"><a rel="nofollow" class="external text" href="http://nla.gov.au/nla.news-article130565761">"Obituary: Lady Titterton, 1921–1995"</a>. <i><a href="/wiki/Canberra_Times" class="mw-redirect" title="Canberra Times">Canberra Times</a></i>. National Library of Australia. 23 October 1995. p.&#160;2. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200314190408/http://nla.gov.au/nla.news-article130565761">Archived</a> from the original on 14 March 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">21 December</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Canberra+Times&amp;rft.atitle=Obituary%3A+Lady+Titterton%2C+1921%E2%80%931995&amp;rft.pages=2&amp;rft.date=1995-10-23&amp;rft_id=http%3A%2F%2Fnla.gov.au%2Fnla.news-article130565761&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHawkins1961180-95"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961180_95-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;180.</span> </li> <li id="cite_note-FOOTNOTESteeper20031–3-96"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESteeper20031–3_96-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSteeper2003">Steeper 2003</a>, pp.&#160;1–3.</span> </li> <li id="cite_note-FOOTNOTEConant200584–85-97"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEConant200584–85_97-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFConant2005">Conant 2005</a>, pp.&#160;84–85.</span> </li> <li id="cite_note-FOOTNOTEHawkins196132,_36-98"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196132,_36_98-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;32, 36.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199392-99"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199392_99-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;92.</span> </li> <li id="cite_note-FOOTNOTEHawkins196184,_101,_124,_148-100"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196184,_101,_124,_148_100-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;84, 101, 124, 148.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199393–94-101"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199393–94_101-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;93–94.</span> </li> <li id="cite_note-FOOTNOTEHawkins196127–30-102"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins196127–30_102-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins196127–30_102-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;27–30.</span> </li> <li id="cite_note-103"><span class="mw-cite-backlink"><b><a href="#cite_ref-103">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSharp1984" class="citation journal cs1">Sharp, D.H. (1984). <a rel="nofollow" class="external text" href="https://digital.library.unt.edu/ark:/67531/metadc1104671/">"An Overview of Rayleigh-Taylor Instability"</a>. <i>Physica D</i>. <b>12</b> (1–3): 3–18. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1984PhyD...12....3S">1984PhyD...12....3S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0167-2789%2884%2990510-4">10.1016/0167-2789(84)90510-4</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200807093219/https://digital.library.unt.edu/ark:/67531/metadc1104671/">Archived</a> from the original on 7 August 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">6 December</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Physica+D&amp;rft.atitle=An+Overview+of+Rayleigh-Taylor+Instability&amp;rft.volume=12&amp;rft.issue=1%E2%80%933&amp;rft.pages=3-18&amp;rft.date=1984&amp;rft_id=info%3Adoi%2F10.1016%2F0167-2789%2884%2990510-4&amp;rft_id=info%3Abibcode%2F1984PhyD...12....3S&amp;rft.aulast=Sharp&amp;rft.aufirst=D.H.&amp;rft_id=https%3A%2F%2Fdigital.library.unt.edu%2Fark%3A%2F67531%2Fmetadc1104671%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTESzasz199218–19-104"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESzasz199218–19_104-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSzasz1992">Szasz 1992</a>, pp.&#160;18–19.</span> </li> <li id="cite_note-FOOTNOTESzasz199246–49-105"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESzasz199246–49_105-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSzasz1992">Szasz 1992</a>, pp.&#160;46–49.</span> </li> <li id="cite_note-FOOTNOTETruslowSmith19613-106"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslowSmith19613_106-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslowSmith1961">Truslow &amp; Smith 1961</a>, p.&#160;3.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993111–114-107"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993111–114_107-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;111–114.</span> </li> <li id="cite_note-FOOTNOTEHawkins196174–75-108"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196174–75_108-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;74–75.</span> </li> <li id="cite_note-FOOTNOTESerberCrease1998104-109"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTESerberCrease1998104_109-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFSerberCrease1998">Serber &amp; Crease 1998</a>, p.&#160;104.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78-110"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78_110-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199375–78_110-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;75–78.</span> </li> <li id="cite_note-FOOTNOTEHawkins196185–88-111"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196185–88_111-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;85–88.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184-112"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184_112-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993183–184_112-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;183–184.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961103–104-113"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961103–104_113-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961103–104_113-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;103–104.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199378–80-114"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199378–80_114-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;78–80.</span> </li> <li id="cite_note-115"><span class="mw-cite-backlink"><b><a href="#cite_ref-115">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.asap.unimelb.edu.au/bsparcs/aasmemoirs/titterto.htm">"Ernest William Titterton 1916–1990"</a>. <a href="/wiki/Australian_Academy_of_Science" title="Australian Academy of Science">Australian Academy of Science</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190306061255/http://www.asap.unimelb.edu.au/bsparcs/aasmemoirs/titterto.htm">Archived</a> from the original on 6 March 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">28 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Ernest+William+Titterton+1916%E2%80%931990&amp;rft.pub=Australian+Academy+of+Science&amp;rft_id=http%3A%2F%2Fwww.asap.unimelb.edu.au%2Fbsparcs%2Faasmemoirs%2Ftitterto.htm&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHawkins196198–99-116"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196198–99_116-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;98–99.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961124–125-117"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961124–125_117-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961124–125_117-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;124–125.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199382–85-118"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199382–85_118-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;82–85.</span> </li> <li id="cite_note-119"><span class="mw-cite-backlink"><b><a href="#cite_ref-119">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, p.&#160;163 "Out of the Review Committee’s work came one important technical contribution when [Edwin L.] Rose pointed out, in connection with the Thin Man, that the durability of the gun was quite immaterial to success, since it would be destroyed in the explosion anyway. Self-evident as this seemed once it was mentioned, it had not previously occurred to us. Now we could make drastic reductions in our estimates of the Thin Man’s size and weight. Because the gun-type bomb thus became militarily practical at an early date, work on it could go ahead on an orderly and not too hurried basis."</span> </li> <li id="cite_note-FOOTNOTEHawkins1961127–128-120"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961127–128_120-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;127–128.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993114–115-121"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993114–115_121-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;114–115.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961129–134-122"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961129–134_122-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961129–134_122-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;129–134.</span> </li> <li id="cite_note-FOOTNOTERamsey2012344–345-123"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERamsey2012344–345_123-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRamsey2012">Ramsey 2012</a>, pp.&#160;344–345.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962109-124"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962109_124-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;109.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962211-125"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962211_125-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;211.</span> </li> <li id="cite_note-FOOTNOTEBakerHeckerHarbur1983141-126"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBakerHeckerHarbur1983141_126-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBakerHeckerHarbur1983">Baker, Hecker &amp; Harbur 1983</a>, p.&#160;141.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993220–221-127"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993220–221_127-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;220–221.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993223–227-128"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993223–227_128-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;223–227.</span> </li> <li id="cite_note-FOOTNOTEBakerHeckerHarbur1983146-129"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBakerHeckerHarbur1983146_129-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBakerHeckerHarbur1983">Baker, Hecker &amp; Harbur 1983</a>, p.&#160;146.</span> </li> <li id="cite_note-130"><span class="mw-cite-backlink"><b><a href="#cite_ref-130">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBohrWheeler1939" class="citation journal cs1"><a href="/wiki/Niels_Bohr" title="Niels Bohr">Bohr, Niels</a>; <a href="/wiki/John_Archibald_Wheeler" title="John Archibald Wheeler">Wheeler, John Archibald</a> (September 1939). <a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRev.56.426">"The Mechanism of Nuclear Fission"</a>. <i><a href="/wiki/Physical_Review" title="Physical Review">Physical Review</a></i>. <b>56</b> (5). American Physical Society: 426–450. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1939PhRv...56..426B">1939PhRv...56..426B</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRev.56.426">10.1103/PhysRev.56.426</a></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Physical+Review&amp;rft.atitle=The+Mechanism+of+Nuclear+Fission&amp;rft.volume=56&amp;rft.issue=5&amp;rft.pages=426-450&amp;rft.date=1939-09&amp;rft_id=info%3Adoi%2F10.1103%2FPhysRev.56.426&amp;rft_id=info%3Abibcode%2F1939PhRv...56..426B&amp;rft.aulast=Bohr&amp;rft.aufirst=Niels&amp;rft.au=Wheeler%2C+John+Archibald&amp;rft_id=https%3A%2F%2Fdoi.org%2F10.1103%252FPhysRev.56.426&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-131"><span class="mw-cite-backlink"><b><a href="#cite_ref-131">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLibby1939" class="citation journal cs1">Libby, W. F. (1939). "Stability of Uranium and Thorium for Natural Fission". <i><a href="/wiki/Physical_Review" title="Physical Review">Physical Review</a></i>. <b>55</b> (12): 1269. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1939PhRv...55.1269L">1939PhRv...55.1269L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRev.55.1269">10.1103/PhysRev.55.1269</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Physical+Review&amp;rft.atitle=Stability+of+Uranium+and+Thorium+for+Natural+Fission&amp;rft.volume=55&amp;rft.issue=12&amp;rft.pages=1269&amp;rft.date=1939&amp;rft_id=info%3Adoi%2F10.1103%2FPhysRev.55.1269&amp;rft_id=info%3Abibcode%2F1939PhRv...55.1269L&amp;rft.aulast=Libby&amp;rft.aufirst=W.+F.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEFrisch1979129-132"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEFrisch1979129_132-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFFrisch1979">Frisch 1979</a>, p.&#160;129.</span> </li> <li id="cite_note-133"><span class="mw-cite-backlink"><b><a href="#cite_ref-133">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFScharff-GoldhaberKlaiber1946" class="citation journal cs1">Scharff-Goldhaber, G.; Klaiber, G. S. (1946). "Spontaneous Emission of Neutrons from Uranium". <i><a href="/wiki/Physical_Review" title="Physical Review">Physical Review</a></i>. <b>70</b> (3–4): 229. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1946PhRv...70..229S">1946PhRv...70..229S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRev.70.229.2">10.1103/PhysRev.70.229.2</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Physical+Review&amp;rft.atitle=Spontaneous+Emission+of+Neutrons+from+Uranium&amp;rft.volume=70&amp;rft.issue=3%E2%80%934&amp;rft.pages=229&amp;rft.date=1946&amp;rft_id=info%3Adoi%2F10.1103%2FPhysRev.70.229.2&amp;rft_id=info%3Abibcode%2F1946PhRv...70..229S&amp;rft.aulast=Scharff-Goldhaber&amp;rft.aufirst=G.&amp;rft.au=Klaiber%2C+G.+S.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962250–251-134"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962250–251_134-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;250–251.</span> </li> <li id="cite_note-135"><span class="mw-cite-backlink"><b><a href="#cite_ref-135">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSegrè1952" class="citation journal cs1">Segrè, Emilio (1952). "Spontaneous Fission". <i>Physical Review</i>. <b>86</b> (1): 21–28. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1952PhRv...86...21S">1952PhRv...86...21S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRev.86.21">10.1103/PhysRev.86.21</a>. <q>The number of neutrons emitted per spontaneous fission of uranium-238 has also been measured and found to be 2.2±0.3.</q></cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Physical+Review&amp;rft.atitle=Spontaneous+Fission&amp;rft.volume=86&amp;rft.issue=1&amp;rft.pages=21-28&amp;rft.date=1952&amp;rft_id=info%3Adoi%2F10.1103%2FPhysRev.86.21&amp;rft_id=info%3Abibcode%2F1952PhRv...86...21S&amp;rft.aulast=Segr%C3%A8&amp;rft.aufirst=Emilio&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993229–233-136"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993229–233_136-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;229–233.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–237-137"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–237_137-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;233–237.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962241-138"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962241_138-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;241.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–239-139"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993233–239_139-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;233–239.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993243–245-140"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993243–245_140-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;243–245.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993242–244-141"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993242–244_141-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;242–244.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90-142"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90_142-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199386–90_142-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;86–90.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962312–313-143"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962312–313_143-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;312–313.</span> </li> <li id="cite_note-FOOTNOTEHawkins196174-144"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196174_144-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;74.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993129–130-145"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993129–130_145-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;129–130.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993130–133-146"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993130–133_146-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;130–133.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993137–139-147"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993137–139_147-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;137–139.</span> </li> <li id="cite_note-148"><span class="mw-cite-backlink"><b><a href="#cite_ref-148">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOppenheimer1944" class="citation web cs1">Oppenheimer, J. Robert (18 July 1944). <a rel="nofollow" class="external text" href="https://www.osti.gov/opennet/servlets/purl/16137151.pdf">"Memo to General Leslie Groves"</a> <span class="cs1-format">(PDF)</span>. Opennet (Department of Energy), Accession No. ALMD4407152167. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20231204050929/https://www.osti.gov/opennet/servlets/purl/16137151.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 4 December 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">20 October</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Memo+to+General+Leslie+Groves&amp;rft.pub=Opennet+%28Department+of+Energy%29%2C+Accession+No.+ALMD4407152167&amp;rft.date=1944-07-18&amp;rft.aulast=Oppenheimer&amp;rft.aufirst=J.+Robert&amp;rft_id=https%3A%2F%2Fwww.osti.gov%2Fopennet%2Fservlets%2Fpurl%2F16137151.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245–248-149"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245–248_149-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;245–248.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962311-150"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962311_150-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;311.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245-151"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993245_151-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;245.</span> </li> <li id="cite_note-FOOTNOTEHawkins196184-152"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins196184_152-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;84.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993162-153"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993162_153-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;162.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961214–215-154"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961214–215_154-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;214–215.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296-155"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296_155-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993294–296_155-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;294–296.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993161,_270–271,_307–308-156"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993161,_270–271,_307–308_156-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;161, 270–271, 307–308.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993299-157"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993299_157-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;299.</span> </li> <li id="cite_note-FOOTNOTEHansen1995bV-123-158"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHansen1995bV-123_158-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHansen1995bV-123_158-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHansen1995bV-123_158-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHansen1995b">Hansen (1995b)</a>, p.&#160;V-123.</span> </li> <li id="cite_note-FOOTNOTERhodes1995195-159"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1995195_159-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1995">Rhodes 1995</a>, p.&#160;195.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993301–307-160"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993301–307_160-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;301–307.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993148–154-161"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993148–154_161-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;148–154.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961203-162"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961203_162-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;203.</span> </li> <li id="cite_note-FOOTNOTEHansen1995aI-298-163"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHansen1995aI-298_163-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHansen1995a">Hansen 1995a</a>, p.&#160;I-298.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962235-164"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962235_164-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, p.&#160;235.</span> </li> <li id="cite_note-FOOTNOTEGilbert19693–4-165"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGilbert19693–4_165-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGilbert1969">Gilbert 1969</a>, pp.&#160;3–4.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993308–310-166"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993308–310_166-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;308–310.</span> </li> <li id="cite_note-FOOTNOTEBakerHeckerHarbur1983144–145-167"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEBakerHeckerHarbur1983144–145_167-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFBakerHeckerHarbur1983">Baker, Hecker &amp; Harbur 1983</a>, pp.&#160;144–145.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993288-168"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993288_168-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;288.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993290-169"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993290_169-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;290.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993330–331-170"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993330–331_170-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;330–331.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993250-171"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993250_171-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;250.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961221-172"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961221_172-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;221.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961223-173"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961223_173-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;223.</span> </li> <li id="cite_note-FOOTNOTERhodes1986541-174"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986541_174-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, p.&#160;541.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993218–219-175"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993218–219_175-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;218–219.</span> </li> <li id="cite_note-FOOTNOTEJones1985143-176"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985143_176-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;143.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–211-177"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–211_177-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;210–211.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993181-178"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993181_178-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;181.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213-179"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213_179-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993210–213_179-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;210–213.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961148-180"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961148_180-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;148.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993252-181"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993252_181-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;252.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961224–225-182"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961224–225_182-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961224–225_182-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961224–225_182-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;224–225.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993257-183"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993257_183-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;257.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993255–256-184"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993255–256_184-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;255–256.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993262-185"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993262_185-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;262.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265-186"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993265_186-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;265.</span> </li> <li id="cite_note-FOOTNOTECoster-Mullen201230-187"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECoster-Mullen201230_187-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCoster-Mullen2012">Coster-Mullen 2012</a>, p.&#160;30.</span> </li> <li id="cite_note-FOOTNOTEHansen1995b111–112-188"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHansen1995b111–112_188-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHansen1995b">Hansen 1995b</a>, pp.&#160;111–112.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993293-189"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993293_189-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;293.</span> </li> <li id="cite_note-FOOTNOTEHansen1995b113-190"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHansen1995b113_190-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHansen1995b113_190-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHansen1995b">Hansen 1995b</a>, p.&#160;113.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993333-191"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993333_191-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;333.</span> </li> <li id="cite_note-FOOTNOTEBunker1983124–125-192"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEBunker1983124–125_192-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEBunker1983124–125_192-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFBunker1983">Bunker 1983</a>, pp.&#160;124–125.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961116–120-193"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961116–120_193-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961116–120_193-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;116–120.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961165–166-194"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961165–166_194-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;165–166.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203-195"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993199–203_195-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;199–203.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall199388-196"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall199388_196-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;88.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961101-197"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961101_197-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;101.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961162–163-198"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961162–163_198-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;162–163.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961213-199"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961213_199-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;213.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961218–219-200"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961218–219_200-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961218–219_200-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;218–219.</span> </li> <li id="cite_note-201"><span class="mw-cite-backlink"><b><a href="#cite_ref-201">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20161112141937/http://www.nuclear-power.net/nuclear-power/reactor-physics/atomic-nuclear-physics/fundamental-particles/neutron/neutron-sources/">"Neutron Sources"</a>. Nuclear Power. Archived from <a rel="nofollow" class="external text" href="http://www.nuclear-power.net/nuclear-power/reactor-physics/atomic-nuclear-physics/fundamental-particles/neutron/neutron-sources/">the original</a> on 12 November 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">12 November</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Neutron+Sources&amp;rft.pub=Nuclear+Power&amp;rft_id=http%3A%2F%2Fwww.nuclear-power.net%2Fnuclear-power%2Freactor-physics%2Fatomic-nuclear-physics%2Ffundamental-particles%2Fneutron%2Fneutron-sources%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHawkins196195–98-202"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins196195–98_202-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins196195–98_202-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins196195–98_202-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;95–98.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204-203"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204_203-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993203–204_203-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;203–204.</span> </li> <li id="cite_note-FOOTNOTEDash1973296–299-204"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEDash1973296–299_204-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFDash1973">Dash 1973</a>, pp.&#160;296–299.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961214–216-205"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHawkins1961214–216_205-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, pp.&#160;214–216.</span> </li> <li id="cite_note-FOOTNOTETruslowSmith196160-206"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslowSmith196160_206-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslowSmith1961">Truslow &amp; Smith 1961</a>, p.&#160;60.</span> </li> <li id="cite_note-PBS-207"><span class="mw-cite-backlink">^ <a href="#cite_ref-PBS_207-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-PBS_207-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.pbs.org/wgbh/amex/bomb/peopleevents/pandeAMEX71.html">"American Experience . Race for the Superbomb . Super Conference"</a>. <a href="/wiki/PBS" title="PBS">PBS</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160828134429/http://www.pbs.org/wgbh/amex/bomb/peopleevents/pandeAMEX71.html">Archived</a> from the original on 28 August 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">28 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=American+Experience+.+Race+for+the+Superbomb+.+Super+Conference&amp;rft.pub=PBS&amp;rft_id=https%3A%2F%2Fwww.pbs.org%2Fwgbh%2Famex%2Fbomb%2Fpeopleevents%2FpandeAMEX71.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962631–632-208"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962631–632_208-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;631–632.</span> </li> <li id="cite_note-FOOTNOTEJones1985465-209"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985465_209-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;465.</span> </li> <li id="cite_note-FOOTNOTEHewlettAnderson1962318–319-210"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettAnderson1962318–319_210-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettAnderson1962">Hewlett &amp; Anderson 1962</a>, pp.&#160;318–319.</span> </li> <li id="cite_note-FOOTNOTEJones1985478–481-211"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985478–481_211-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;478–481.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993174–175-212"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993174–175_212-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;174–175.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993365–367-213"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993365–367_213-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;365–367.</span> </li> <li id="cite_note-FOOTNOTEJones1985512-214"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones1985512_214-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones1985512_214-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;512.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993360–362-215"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993360–362_215-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;360–362.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993367–370-216"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993367–370_216-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;367–370.</span> </li> <li id="cite_note-FOOTNOTEJones1985514–517-217"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEJones1985514–517_217-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEJones1985514–517_217-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;514–517.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993372–374-218"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993372–374_218-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;372–374.</span> </li> <li id="cite_note-219"><span class="mw-cite-backlink"><b><a href="#cite_ref-219">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSilvera2023" class="citation web cs1">Silvera, Ian (26 May 2023). <a rel="nofollow" class="external text" href="https://www.news-future.com/p/oppenheimer-atomic-bill-and-the-explosive">"Oppenheimer, Atomic Bill and the Explosive Birth of Science Journalism"</a>. <i>www.news-future.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230604234139/https://www.news-future.com/p/oppenheimer-atomic-bill-and-the-explosive">Archived</a> from the original on 4 June 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">12 June</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=www.news-future.com&amp;rft.atitle=Oppenheimer%2C+Atomic+Bill+and+the+Explosive+Birth+of+Science+Journalism&amp;rft.date=2023-05-26&amp;rft.aulast=Silvera&amp;rft.aufirst=Ian&amp;rft_id=https%3A%2F%2Fwww.news-future.com%2Fp%2Foppenheimer-atomic-bill-and-the-explosive&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTERamsey2012340-220"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERamsey2012340_220-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRamsey2012">Ramsey 2012</a>, p.&#160;340.</span> </li> <li id="cite_note-org-221"><span class="mw-cite-backlink">^ <a href="#cite_ref-org_221-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-org_221-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20140204013045/http://physicsnow.org/history/acap/institutions/manhattan.jsp">"The Manhattan Project"</a>. Array of Contemporary American Physicists. Archived from <a rel="nofollow" class="external text" href="http://physicsnow.org/history/acap/institutions/manhattan.jsp">the original</a> on 4 February 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">8 February</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=The+Manhattan+Project&amp;rft.pub=Array+of+Contemporary+American+Physicists&amp;rft_id=http%3A%2F%2Fphysicsnow.org%2Fhistory%2Facap%2Finstitutions%2Fmanhattan.jsp&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTERamsey2012346-222"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTERamsey2012346_222-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTERamsey2012346_222-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFRamsey2012">Ramsey 2012</a>, p.&#160;346.</span> </li> <li id="cite_note-FOOTNOTECampbell2005143-223"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell2005143_223-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;143.</span> </li> <li id="cite_note-FOOTNOTECampbell2005156-224"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell2005156_224-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;156.</span> </li> <li id="cite_note-FOOTNOTEHawkins1961286-225"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHawkins1961286_225-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHawkins1961286_225-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHawkins1961">Hawkins 1961</a>, p.&#160;286.</span> </li> <li id="cite_note-FOOTNOTECampbell2005157-226"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell2005157_226-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;157.</span> </li> <li id="cite_note-FOOTNOTERuss199030-227"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199030_227-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, p.&#160;30.</span> </li> <li id="cite_note-FOOTNOTERuss199052-228"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199052_228-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, p.&#160;52.</span> </li> <li id="cite_note-FOOTNOTECampbell200527-229"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell200527_229-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;27.</span> </li> <li id="cite_note-FOOTNOTECampbell200550-230"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell200550_230-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;50.</span> </li> <li id="cite_note-FOOTNOTECampbell200546,_80-231"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell200546,_80_231-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, pp.&#160;46, 80.</span> </li> <li id="cite_note-FOOTNOTECoster-Mullen2012100–101-232"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECoster-Mullen2012100–101_232-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCoster-Mullen2012">Coster-Mullen 2012</a>, pp.&#160;100–101.</span> </li> <li id="cite_note-FOOTNOTERuss199055-233"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199055_233-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, p.&#160;55.</span> </li> <li id="cite_note-FOOTNOTERhodes1986691-234"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERhodes1986691_234-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRhodes1986">Rhodes 1986</a>, p.&#160;691.</span> </li> <li id="cite_note-FOOTNOTECampbell200541-235"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell200541_235-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, p.&#160;41.</span> </li> <li id="cite_note-FOOTNOTERuss199056–57-236"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199056–57_236-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, pp.&#160;56–57.</span> </li> <li id="cite_note-FOOTNOTECampbell200538–40-237"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECampbell200538–40_237-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCampbell2005">Campbell 2005</a>, pp.&#160;38–40.</span> </li> <li id="cite_note-FOOTNOTECoster-Mullen201234–35-238"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTECoster-Mullen201234–35_238-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFCoster-Mullen2012">Coster-Mullen 2012</a>, pp.&#160;34–35.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993393-239"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993393_239-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, p.&#160;393.</span> </li> <li id="cite_note-240"><span class="mw-cite-backlink"><b><a href="#cite_ref-240">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMcLellan" class="citation news cs1">McLellan, Dennis. <a rel="nofollow" class="external text" href="https://archive.seattletimes.com/archive/20030824/marquardtobit24/george-marquardt-us-war-pilot-over-hiroshima-dies-at-84">"George Marquardt, U.S. war pilot over Hiroshima, dies at 84"</a>. <i><a href="/wiki/The_Seattle_Times" title="The Seattle Times">The Seattle Times</a></i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140219012052/http://community.seattletimes.nwsource.com/archive/?date=20030824&amp;slug=marquardtobit24">Archived</a> from the original on 19 February 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">2 February</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=The+Seattle+Times&amp;rft.atitle=George+Marquardt%2C+U.S.+war+pilot+over+Hiroshima%2C+dies+at+84&amp;rft.aulast=McLellan&amp;rft.aufirst=Dennis&amp;rft_id=https%3A%2F%2Farchive.seattletimes.com%2Farchive%2F20030824%2Fmarquardtobit24%2Fgeorge-marquardt-us-war-pilot-over-hiroshima-dies-at-84&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEAlvarezTrower198766-241"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEAlvarezTrower198766_241-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFAlvarezTrower1987">Alvarez &amp; Trower 1987</a>, p.&#160;66.</span> </li> <li id="cite_note-FOOTNOTERuss199060-242"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199060_242-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, p.&#160;60.</span> </li> <li id="cite_note-FOOTNOTERuss199064–65-243"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTERuss199064–65_243-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFRuss1990">Russ 1990</a>, pp.&#160;64–65.</span> </li> <li id="cite_note-eyewitness-244"><span class="mw-cite-backlink"><b><a href="#cite_ref-eyewitness_244-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLaurence" class="citation web cs1"><a href="/wiki/William_L._Laurence" title="William L. Laurence">Laurence, William L.</a> <a rel="nofollow" class="external text" href="http://www.atomicarchive.com/Docs/Hiroshima/Nagasaki.shtml">"Eyewitness Account of Atomic Bomb Over Nagasaki"</a>. National Science Digital Library. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110203233201/http://www.atomicarchive.com/Docs/Hiroshima/Nagasaki.shtml">Archived</a> from the original on 3 February 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">18 March</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Eyewitness+Account+of+Atomic+Bomb+Over+Nagasaki&amp;rft.pub=National+Science+Digital+Library&amp;rft.aulast=Laurence&amp;rft.aufirst=William+L.&amp;rft_id=http%3A%2F%2Fwww.atomicarchive.com%2FDocs%2FHiroshima%2FNagasaki.shtml&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-remembered-245"><span class="mw-cite-backlink"><b><a href="#cite_ref-remembered_245-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.hiroshima-remembered.com/history/nagasaki/page3.html">"The Story of Nagasaki"</a>. National Science Digital Library. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121225223342/http://hiroshima-remembered.com/history/nagasaki/page3.html">Archived</a> from the original on 25 December 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">28 March</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=The+Story+of+Nagasaki&amp;rft.pub=National+Science+Digital+Library&amp;rft_id=http%3A%2F%2Fwww.hiroshima-remembered.com%2Fhistory%2Fnagasaki%2Fpage3.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEWarren1966879-246"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEWarren1966879_246-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEWarren1966879_246-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFWarren1966">Warren 1966</a>, p.&#160;879.</span> </li> <li id="cite_note-247"><span class="mw-cite-backlink"><b><a href="#cite_ref-247">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20161114165520/http://www.atomicheritage.org/profile/james-f-nolan">"James F. Nolan"</a>. Atomic Heritage Foundation. Archived from <a rel="nofollow" class="external text" href="http://www.atomicheritage.org/profile/james-f-nolan">the original</a> on 14 November 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">14 November</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=James+F.+Nolan&amp;rft.pub=Atomic+Heritage+Foundation&amp;rft_id=http%3A%2F%2Fwww.atomicheritage.org%2Fprofile%2Fjames-f-nolan&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEJones1985424–426-248"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985424–426_248-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;424–426.</span> </li> <li id="cite_note-FOOTNOTEWarren1966881-249"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEWarren1966881_249-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFWarren1966">Warren 1966</a>, p.&#160;881.</span> </li> <li id="cite_note-FOOTNOTEHacker198768–69-250"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHacker198768–69_250-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHacker1987">Hacker 1987</a>, pp.&#160;68–69.</span> </li> <li id="cite_note-FOOTNOTEHacker198771-251"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHacker198771_251-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHacker1987">Hacker 1987</a>, p.&#160;71.</span> </li> <li id="cite_note-252"><span class="mw-cite-backlink"><b><a href="#cite_ref-252">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWellenstein2015" class="citation web cs1">Wellenstein, Alex (15 February 2015). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20161115015521/http://blog.nuclearsecrecy.com/2015/02/13/how-to-die-at-los-alamos/">"How to die at Los Alamos"</a>. Restricted Data. Archived from <a rel="nofollow" class="external text" href="http://blog.nuclearsecrecy.com/2015/02/13/how-to-die-at-los-alamos/">the original</a> on 15 November 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">10 January</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=How+to+die+at+Los+Alamos&amp;rft.pub=Restricted+Data&amp;rft.date=2015-02-15&amp;rft.aulast=Wellenstein&amp;rft.aufirst=Alex&amp;rft_id=http%3A%2F%2Fblog.nuclearsecrecy.com%2F2015%2F02%2F13%2Fhow-to-die-at-los-alamos%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEJones1985267-253"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985267_253-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, p.&#160;267.</span> </li> <li id="cite_note-FOOTNOTEConant2005253-254"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEConant2005253_254-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFConant2005">Conant 2005</a>, p.&#160;253.</span> </li> <li id="cite_note-FOOTNOTEJones1985258–260-255"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985258–260_255-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;258–260.</span> </li> <li id="cite_note-FOOTNOTEJones1985261–265-256"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEJones1985261–265_256-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFJones1985">Jones 1985</a>, pp.&#160;261–265.</span> </li> <li id="cite_note-FOOTNOTEGroves1962142–145-257"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEGroves1962142–145_257-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFGroves1962">Groves 1962</a>, pp.&#160;142–145.</span> </li> <li id="cite_note-FOOTNOTEHewlettDuncan1969312–314-258"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettDuncan1969312–314_258-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettDuncan1969">Hewlett &amp; Duncan 1969</a>, pp.&#160;312–314.</span> </li> <li id="cite_note-FOOTNOTEHewlettDuncan1969472-259"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettDuncan1969472_259-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettDuncan1969">Hewlett &amp; Duncan 1969</a>, p.&#160;472.</span> </li> <li id="cite_note-260"><span class="mw-cite-backlink"><b><a href="#cite_ref-260">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBroad2007" class="citation news cs1">Broad, William J. (12 November 2007). <a rel="nofollow" class="external text" href="https://www.nytimes.com/2007/11/12/us/12koval.html">"A Spy's Path: Iowa to A-Bomb to Kremlin Honor"</a>. <i><a href="/wiki/The_New_York_Times" title="The New York Times">The New York Times</a></i>. pp.&#160;1–2. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180117040412/http://www.nytimes.com/2007/11/12/us/12koval.html">Archived</a> from the original on 17 January 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">2 July</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=The+New+York+Times&amp;rft.atitle=A+Spy%27s+Path%3A+Iowa+to+A-Bomb+to+Kremlin+Honor&amp;rft.pages=1-2&amp;rft.date=2007-11-12&amp;rft.aulast=Broad&amp;rft.aufirst=William+J.&amp;rft_id=https%3A%2F%2Fwww.nytimes.com%2F2007%2F11%2F12%2Fus%2F12koval.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993625–626-261"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993625–626_261-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;625–626.</span> </li> <li id="cite_note-FOOTNOTEEbinger200682–83-262"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEEbinger200682–83_262-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFEbinger2006">Ebinger 2006</a>, pp.&#160;82–83.</span> </li> <li id="cite_note-FOOTNOTEAgnewSchreiber19989-263"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEAgnewSchreiber19989_263-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFAgnewSchreiber1998">Agnew &amp; Schreiber 1998</a>, p.&#160;9.</span> </li> <li id="cite_note-FOOTNOTEEbinger200698-264"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEEbinger200698_264-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFEbinger2006">Ebinger 2006</a>, p.&#160;98.</span> </li> <li id="cite_note-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402-265"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402_265-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEHoddesonHenriksenMeadeWestfall1993398–402_265-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFHoddesonHenriksenMeadeWestfall1993">Hoddeson et al. 1993</a>, pp.&#160;398–402.</span> </li> <li id="cite_note-FOOTNOTEAgnewSchreiber19984-266"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEAgnewSchreiber19984_266-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFAgnewSchreiber1998">Agnew &amp; Schreiber 1998</a>, p.&#160;4.</span> </li> <li id="cite_note-FOOTNOTEAgnewSchreiber19985-267"><span class="mw-cite-backlink">^ <a href="#cite_ref-FOOTNOTEAgnewSchreiber19985_267-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FOOTNOTEAgnewSchreiber19985_267-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="#CITEREFAgnewSchreiber1998">Agnew &amp; Schreiber 1998</a>, p.&#160;5.</span> </li> <li id="cite_note-FOOTNOTETruslowSmith196195–96-268"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslowSmith196195–96_268-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslowSmith1961">Truslow &amp; Smith 1961</a>, pp.&#160;95–96.</span> </li> <li id="cite_note-FOOTNOTEAgnewSchreiber19986-269"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEAgnewSchreiber19986_269-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFAgnewSchreiber1998">Agnew &amp; Schreiber 1998</a>, p.&#160;6.</span> </li> <li id="cite_note-FOOTNOTETruslowSmith196122–23-270"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslowSmith196122–23_270-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslowSmith1961">Truslow &amp; Smith 1961</a>, p.&#160;22–23.</span> </li> <li id="cite_note-271"><span class="mw-cite-backlink"><b><a href="#cite_ref-271">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWellerstein2016" class="citation web cs1">Wellerstein, Alex (25 July 2016). <a rel="nofollow" class="external text" href="http://blog.nuclearsecrecy.com/2016/07/25/operation-crossroads-70/">"Operation Crossroads at 70"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20181025134614/http://blog.nuclearsecrecy.com/2016/07/25/operation-crossroads-70/">Archived</a> from the original on 25 October 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">27 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Operation+Crossroads+at+70&amp;rft.date=2016-07-25&amp;rft.aulast=Wellerstein&amp;rft.aufirst=Alex&amp;rft_id=http%3A%2F%2Fblog.nuclearsecrecy.com%2F2016%2F07%2F25%2Foperation-crossroads-70%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></span> </li> <li id="cite_note-FOOTNOTETruslowSmith1961v-272"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTETruslowSmith1961v_272-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFTruslowSmith1961">Truslow &amp; Smith 1961</a>, p.&#160;v.</span> </li> <li id="cite_note-FOOTNOTEEbinger200689–90-273"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEEbinger200689–90_273-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFEbinger2006">Ebinger 2006</a>, pp.&#160;89–90.</span> </li> <li id="cite_note-FOOTNOTEHewlettDuncan196943-274"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEHewlettDuncan196943_274-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFHewlettDuncan1969">Hewlett &amp; Duncan 1969</a>, p.&#160;43.</span> </li> <li id="cite_note-FOOTNOTEAgnewSchreiber19983-275"><span class="mw-cite-backlink"><b><a href="#cite_ref-FOOTNOTEAgnewSchreiber19983_275-0">^</a></b></span> <span class="reference-text"><a href="#CITEREFAgnewSchreiber1998">Agnew &amp; Schreiber 1998</a>, p.&#160;3.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Project_Y&amp;action=edit&amp;section=24" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin refbegin-columns references-column-width" style="column-width: 24em"> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAgnewSchreiber1998" class="citation book cs1"><a href="/wiki/Harold_Agnew" title="Harold Agnew">Agnew, Harold</a>; <a href="/wiki/Raemer_Schreiber" title="Raemer Schreiber">Schreiber, Raemer E.</a> (1998). <a rel="nofollow" class="external text" href="http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/bradbury-ne.pdf"><i>Norris E. Bradbury 1909–1996: A Biographical Memoir</i></a> <span class="cs1-format">(PDF)</span>. Washington, D.C.: <a href="/wiki/National_Academies_Press" title="National Academies Press">National Academies Press</a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/79388516">79388516</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160303195735/http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/bradbury-ne.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 3 March 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">6 April</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Norris+E.+Bradbury+1909%E2%80%931996%3A+A+Biographical+Memoir&amp;rft.place=Washington%2C+D.C.&amp;rft.pub=National+Academies+Press&amp;rft.date=1998&amp;rft_id=info%3Aoclcnum%2F79388516&amp;rft.aulast=Agnew&amp;rft.aufirst=Harold&amp;rft.au=Schreiber%2C+Raemer+E.&amp;rft_id=http%3A%2F%2Fwww.nasonline.org%2Fpublications%2Fbiographical-memoirs%2Fmemoir-pdfs%2Fbradbury-ne.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAlvarezTrower1987" class="citation book cs1"><a href="/wiki/Luis_W._Alvarez" class="mw-redirect" title="Luis W. Alvarez">Alvarez, Luis W.</a>; Trower, W. Peter (1987). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/discoveringalvar0000alva"><i>Discovering Alvarez: Selected Works of Luis W. Alvarez, with Commentary by his Students and Colleagues</i></a></span>. Chicago: <a href="/wiki/University_of_Chicago_Press" title="University of Chicago Press">University of Chicago Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-226-81304-2" title="Special:BookSources/978-0-226-81304-2"><bdi>978-0-226-81304-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/15791693">15791693</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Discovering+Alvarez%3A+Selected+Works+of+Luis+W.+Alvarez%2C+with+Commentary+by+his+Students+and+Colleagues&amp;rft.place=Chicago&amp;rft.pub=University+of+Chicago+Press&amp;rft.date=1987&amp;rft_id=info%3Aoclcnum%2F15791693&amp;rft.isbn=978-0-226-81304-2&amp;rft.aulast=Alvarez&amp;rft.aufirst=Luis+W.&amp;rft.au=Trower%2C+W.+Peter&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fdiscoveringalvar0000alva&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBakerHeckerHarbur1983" class="citation journal cs1">Baker, Richard D.; Hecker, Siegfried S.; Harbur, Delbert R. (1983). <a rel="nofollow" class="external text" href="http://library.lanl.gov/cgi-bin/getfile?07-16.pdf">"Plutonium: A Wartime Nightmare but a Metallurgist's Dream"</a> <span class="cs1-format">(PDF)</span>. <i>Los Alamos Science</i> (Winter/Spring). Los Alamos National Laboratory: 142–151. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20111017034523/http://library.lanl.gov/cgi-bin/getfile?07-16.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 17 October 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">22 November</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Los+Alamos+Science&amp;rft.atitle=Plutonium%3A+A+Wartime+Nightmare+but+a+Metallurgist%27s+Dream&amp;rft.issue=Winter%2FSpring&amp;rft.pages=142-151&amp;rft.date=1983&amp;rft.aulast=Baker&amp;rft.aufirst=Richard+D.&amp;rft.au=Hecker%2C+Siegfried+S.&amp;rft.au=Harbur%2C+Delbert+R.&amp;rft_id=http%3A%2F%2Flibrary.lanl.gov%2Fcgi-bin%2Fgetfile%3F07-16.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCompton1956" class="citation book cs1"><a href="/wiki/Arthur_Compton" title="Arthur Compton">Compton, Arthur</a> (1956). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/atomicquestperso0000comp"><i>Atomic Quest</i></a></span>. New York: <a href="/wiki/Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/173307">173307</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Atomic+Quest&amp;rft.place=New+York&amp;rft.pub=Oxford+University+Press&amp;rft.date=1956&amp;rft_id=info%3Aoclcnum%2F173307&amp;rft.aulast=Compton&amp;rft.aufirst=Arthur&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fatomicquestperso0000comp&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBethe1991" class="citation book cs1"><a href="/wiki/Hans_Bethe" title="Hans Bethe">Bethe, Hans A.</a> (1991). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/roadfromlosalamo00beth"><i>The Road from Los Alamos</i></a></span>. New York: <a href="/wiki/Simon_%26_Schuster" title="Simon &amp; Schuster">Simon &amp; Schuster</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-671-74012-2" title="Special:BookSources/978-0-671-74012-2"><bdi>978-0-671-74012-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/22661282">22661282</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Road+from+Los+Alamos&amp;rft.place=New+York&amp;rft.pub=Simon+%26+Schuster&amp;rft.date=1991&amp;rft_id=info%3Aoclcnum%2F22661282&amp;rft.isbn=978-0-671-74012-2&amp;rft.aulast=Bethe&amp;rft.aufirst=Hans+A.&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Froadfromlosalamo00beth&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBunker1983" class="citation journal cs1">Bunker, Merle E. (Winter–Spring 1983). <a rel="nofollow" class="external text" href="https://fas.org/sgp/othergov/doe/lanl/pubs/00416628.pdf">"Early Reactors From Fermi's Water Boiler to Novel Power Prototypes"</a> <span class="cs1-format">(PDF)</span>. <i>Los Alamos Science</i>. Los Alamos National Laboratory: 124–131. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160416042718/http://fas.org/sgp/othergov/doe/lanl/pubs/00416628.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 16 April 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">27 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Los+Alamos+Science&amp;rft.atitle=Early+Reactors+From+Fermi%27s+Water+Boiler+to+Novel+Power+Prototypes&amp;rft.chron=winter%E2%80%93spring&amp;rft.pages=124-131&amp;rft.date=1983&amp;rft.aulast=Bunker&amp;rft.aufirst=Merle+E.&amp;rft_id=https%3A%2F%2Ffas.org%2Fsgp%2Fothergov%2Fdoe%2Flanl%2Fpubs%2F00416628.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCampbell2005" class="citation book cs1">Campbell, Richard H. (2005). <i>The Silverplate Bombers: A History and Registry of the Enola Gay and Other B-29s Configured to Carry Atomic Bombs</i>. Jefferson, North Carolina: McFarland &amp; Company. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-7864-2139-8" title="Special:BookSources/978-0-7864-2139-8"><bdi>978-0-7864-2139-8</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/58554961">58554961</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Silverplate+Bombers%3A+A+History+and+Registry+of+the+Enola+Gay+and+Other+B-29s+Configured+to+Carry+Atomic+Bombs&amp;rft.place=Jefferson%2C+North+Carolina&amp;rft.pub=McFarland+%26+Company&amp;rft.date=2005&amp;rft_id=info%3Aoclcnum%2F58554961&amp;rft.isbn=978-0-7864-2139-8&amp;rft.aulast=Campbell&amp;rft.aufirst=Richard+H.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChambers1999" class="citation book cs1">Chambers, Marjorie Bell (1999). <i>The Battle for Civil Rights, or, How Los Alamos Became a County</i>. Los Alamos story. Los Alamos, New Mexico: Los Alamos Historical Society. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-941232-23-4" title="Special:BookSources/978-0-941232-23-4"><bdi>978-0-941232-23-4</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/41185070">41185070</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Battle+for+Civil+Rights%2C+or%2C+How+Los+Alamos+Became+a+County&amp;rft.place=Los+Alamos%2C+New+Mexico&amp;rft.series=Los+Alamos+story&amp;rft.pub=Los+Alamos+Historical+Society&amp;rft.date=1999&amp;rft_id=info%3Aoclcnum%2F41185070&amp;rft.isbn=978-0-941232-23-4&amp;rft.aulast=Chambers&amp;rft.aufirst=Marjorie+Bell&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChristman1998" class="citation book cs1">Christman, Albert B. (1998). <i>Target Hiroshima: Deak Parsons and the Creation of the Atomic Bomb</i>. Annapolis, Maryland: <a href="/wiki/Naval_Institute_Press" class="mw-redirect" title="Naval Institute Press">Naval Institute Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-1-55750-120-2" title="Special:BookSources/978-1-55750-120-2"><bdi>978-1-55750-120-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/38257982">38257982</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Target+Hiroshima%3A+Deak+Parsons+and+the+Creation+of+the+Atomic+Bomb&amp;rft.place=Annapolis%2C+Maryland&amp;rft.pub=Naval+Institute+Press&amp;rft.date=1998&amp;rft_id=info%3Aoclcnum%2F38257982&amp;rft.isbn=978-1-55750-120-2&amp;rft.aulast=Christman&amp;rft.aufirst=Albert+B.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFConant2005" class="citation book cs1"><a href="/wiki/Jennet_Conant" title="Jennet Conant">Conant, Jennet</a> (2005). <a rel="nofollow" class="external text" href="https://archive.org/details/109eastpalacerob00cona"><i>109 East Palace: Robert Oppenheimer and the Secret City of Los Alamos</i></a>. New York: Simon &amp; Schuster. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-7432-5007-8" title="Special:BookSources/978-0-7432-5007-8"><bdi>978-0-7432-5007-8</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=109+East+Palace%3A+Robert+Oppenheimer+and+the+Secret+City+of+Los+Alamos&amp;rft.place=New+York&amp;rft.pub=Simon+%26+Schuster&amp;rft.date=2005&amp;rft.isbn=978-0-7432-5007-8&amp;rft.aulast=Conant&amp;rft.aufirst=Jennet&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2F109eastpalacerob00cona&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCoster-Mullen2012" class="citation book cs1"><a href="/wiki/John_Coster-Mullen" title="John Coster-Mullen">Coster-Mullen, John</a> (2012). <i>Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man</i>. Waukesha, Wisconsin: J. Coster-Mullen. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/298514167">298514167</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Atom+Bombs%3A+The+Top+Secret+Inside+Story+of+Little+Boy+and+Fat+Man&amp;rft.place=Waukesha%2C+Wisconsin&amp;rft.pub=J.+Coster-Mullen&amp;rft.date=2012&amp;rft_id=info%3Aoclcnum%2F298514167&amp;rft.aulast=Coster-Mullen&amp;rft.aufirst=John&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDash1973" class="citation book cs1">Dash, Joan (1973). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/lifeofonesownthr0000dash"><i>A life of One's Own: Three Gifted Women and the Men they Married</i></a></span>. New York: <a href="/wiki/Harper_%26_Row" class="mw-redirect" title="Harper &amp; Row">Harper &amp; Row</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-06-010949-3" title="Special:BookSources/978-0-06-010949-3"><bdi>978-0-06-010949-3</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/606211">606211</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=A+life+of+One%27s+Own%3A+Three+Gifted+Women+and+the+Men+they+Married&amp;rft.place=New+York&amp;rft.pub=Harper+%26+Row&amp;rft.date=1973&amp;rft_id=info%3Aoclcnum%2F606211&amp;rft.isbn=978-0-06-010949-3&amp;rft.aulast=Dash&amp;rft.aufirst=Joan&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Flifeofonesownthr0000dash&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFEbinger2006" class="citation book cs1">Ebinger, Virginia Nylander (2006). <i>Norris E. Bradbury 1909–1997</i>. Los Alamos, New Mexico: Los Alamos Historical Society. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-941232-34-0" title="Special:BookSources/978-0-941232-34-0"><bdi>978-0-941232-34-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/62408863">62408863</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Norris+E.+Bradbury+1909%E2%80%931997&amp;rft.place=Los+Alamos%2C+New+Mexico&amp;rft.pub=Los+Alamos+Historical+Society&amp;rft.date=2006&amp;rft_id=info%3Aoclcnum%2F62408863&amp;rft.isbn=978-0-941232-34-0&amp;rft.aulast=Ebinger&amp;rft.aufirst=Virginia+Nylander&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFineRemington1972" class="citation book cs1">Fine, Lenore; Remington, Jesse A. (1972). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170201142645/https://history.army.mil/html/books/010/10-5/CMH_Pub_10-5.pdf"><i>The Corps of Engineers: Construction in the United States</i></a> <span class="cs1-format">(PDF)</span>. Washington, D.C.: United States Army Center of Military History. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/834187">834187</a>. Archived from <a rel="nofollow" class="external text" href="http://www.history.army.mil/html/books/010/10-5/CMH_Pub_10-5.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 1 February 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">25 August</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Corps+of+Engineers%3A+Construction+in+the+United+States&amp;rft.place=Washington%2C+D.C.&amp;rft.pub=United+States+Army+Center+of+Military+History&amp;rft.date=1972&amp;rft_id=info%3Aoclcnum%2F834187&amp;rft.aulast=Fine&amp;rft.aufirst=Lenore&amp;rft.au=Remington%2C+Jesse+A.&amp;rft_id=http%3A%2F%2Fwww.history.army.mil%2Fhtml%2Fbooks%2F010%2F10-5%2FCMH_Pub_10-5.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFrisch1979" class="citation book cs1"><a href="/wiki/Otto_Robert_Frisch" title="Otto Robert Frisch">Frisch, Otto Robert</a> (1979). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/whatlittleiremem0000fris"><i>What Little I Remember</i></a></span>. New York: <a href="/wiki/Cambridge_University_Press" title="Cambridge University Press">Cambridge University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-521-28010-5" title="Special:BookSources/978-0-521-28010-5"><bdi>978-0-521-28010-5</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/4114334">4114334</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=What+Little+I+Remember&amp;rft.place=New+York&amp;rft.pub=Cambridge+University+Press&amp;rft.date=1979&amp;rft_id=info%3Aoclcnum%2F4114334&amp;rft.isbn=978-0-521-28010-5&amp;rft.aulast=Frisch&amp;rft.aufirst=Otto+Robert&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fwhatlittleiremem0000fris&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGilbert1969" class="citation book cs1">Gilbert, Keith V. (1969). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190412054801/https://www.eecap.org/PDF_Files/Ohio/Dayton_Project/History/HISTORY_OF_THE_DAYTON_PROJECT.pdf"><i>History of the Dayton Project</i></a> <span class="cs1-format">(PDF)</span>. Miamisburg, Ohio: Mound Laboratory, Atomic Energy Commission. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/650540359">650540359</a>. Archived from <a rel="nofollow" class="external text" href="http://www.eecap.org/PDF_Files/Ohio/Dayton_Project/History/HISTORY_OF_THE_DAYTON_PROJECT.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 12 April 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">31 October</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=History+of+the+Dayton+Project&amp;rft.place=Miamisburg%2C+Ohio&amp;rft.pub=Mound+Laboratory%2C+Atomic+Energy+Commission&amp;rft.date=1969&amp;rft_id=info%3Aoclcnum%2F650540359&amp;rft.aulast=Gilbert&amp;rft.aufirst=Keith+V.&amp;rft_id=http%3A%2F%2Fwww.eecap.org%2FPDF_Files%2FOhio%2FDayton_Project%2FHistory%2FHISTORY_OF_THE_DAYTON_PROJECT.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGowing1964" class="citation book cs1"><a href="/wiki/Margaret_Gowing" title="Margaret Gowing">Gowing, Margaret</a> (1964). <i>Britain and Atomic Energy, 1935–1945</i>. London: <a href="/wiki/Macmillan_Publishing" class="mw-redirect" title="Macmillan Publishing">Macmillan Publishing</a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/3195209">3195209</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Britain+and+Atomic+Energy%2C+1935%E2%80%931945&amp;rft.place=London&amp;rft.pub=Macmillan+Publishing&amp;rft.date=1964&amp;rft_id=info%3Aoclcnum%2F3195209&amp;rft.aulast=Gowing&amp;rft.aufirst=Margaret&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGroves1962" class="citation book cs1"><a href="/wiki/Leslie_Groves" title="Leslie Groves">Groves, Leslie</a> (1962). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/nowitcanbetolds00grov"><i>Now it Can be Told: The Story of the Manhattan Project</i></a></span>. New York: Harper &amp; Row. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-306-70738-4" title="Special:BookSources/978-0-306-70738-4"><bdi>978-0-306-70738-4</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/537684">537684</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Now+it+Can+be+Told%3A+The+Story+of+the+Manhattan+Project&amp;rft.place=New+York&amp;rft.pub=Harper+%26+Row&amp;rft.date=1962&amp;rft_id=info%3Aoclcnum%2F537684&amp;rft.isbn=978-0-306-70738-4&amp;rft.aulast=Groves&amp;rft.aufirst=Leslie&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fnowitcanbetolds00grov&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHacker1987" class="citation book cs1">Hacker, Barton C. (1987). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/dragonstailradia0000hack"><i>The Dragon's Tail: Radiation Safety in the Manhattan Project, 1942–1946</i></a></span>. <a href="/wiki/University_of_California_Press" title="University of California Press">University of California Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-520-05852-1" title="Special:BookSources/978-0-520-05852-1"><bdi>978-0-520-05852-1</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/13794117">13794117</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Dragon%27s+Tail%3A+Radiation+Safety+in+the+Manhattan+Project%2C+1942%E2%80%931946&amp;rft.pub=University+of+California+Press&amp;rft.date=1987&amp;rft_id=info%3Aoclcnum%2F13794117&amp;rft.isbn=978-0-520-05852-1&amp;rft.aulast=Hacker&amp;rft.aufirst=Barton+C.&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fdragonstailradia0000hack&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHansen1995a" class="citation book cs1"><a href="/wiki/Chuck_Hansen" title="Chuck Hansen">Hansen, Chuck</a> (1995a). <i>Volume I: The Development of US Nuclear Weapons</i>. Swords of Armageddon: US Nuclear Weapons Development since 1945. Sunnyvale, California: Chukelea Publications. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-9791915-1-0" title="Special:BookSources/978-0-9791915-1-0"><bdi>978-0-9791915-1-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/231585284">231585284</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Volume+I%3A+The+Development+of+US+Nuclear+Weapons&amp;rft.place=Sunnyvale%2C+California&amp;rft.series=Swords+of+Armageddon%3A+US+Nuclear+Weapons+Development+since+1945&amp;rft.pub=Chukelea+Publications&amp;rft.date=1995&amp;rft_id=info%3Aoclcnum%2F231585284&amp;rft.isbn=978-0-9791915-1-0&amp;rft.aulast=Hansen&amp;rft.aufirst=Chuck&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHansen1995b" class="citation book cs1">Hansen, Chuck (1995b). <i>Volume V: US Nuclear Weapons Histories</i>. Swords of Armageddon: US Nuclear Weapons Development since 1945. Sunnyvale, California: Chukelea Publications. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-9791915-0-3" title="Special:BookSources/978-0-9791915-0-3"><bdi>978-0-9791915-0-3</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/231585284">231585284</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Volume+V%3A+US+Nuclear+Weapons+Histories&amp;rft.place=Sunnyvale%2C+California&amp;rft.series=Swords+of+Armageddon%3A+US+Nuclear+Weapons+Development+since+1945&amp;rft.pub=Chukelea+Publications&amp;rft.date=1995&amp;rft_id=info%3Aoclcnum%2F231585284&amp;rft.isbn=978-0-9791915-0-3&amp;rft.aulast=Hansen&amp;rft.aufirst=Chuck&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHawkins1961" class="citation book cs1"><a href="/wiki/David_Hawkins_(philosopher)" title="David Hawkins (philosopher)">Hawkins, David</a> (1961). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/projectylosalamo0002unse"><i>Manhattan District history, Project Y, the Los Alamos Project – Volume I: Inception until August 1945</i></a></span>. Los Angeles: Tomash Publishers. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-938228-08-0" title="Special:BookSources/978-0-938228-08-0"><bdi>978-0-938228-08-0</bdi></a>. LAMS-2532<span class="reference-accessdate">. Retrieved <span class="nowrap">20 February</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Manhattan+District+history%2C+Project+Y%2C+the+Los+Alamos+Project+%E2%80%93+Volume+I%3A+Inception+until+August+1945&amp;rft.place=Los+Angeles&amp;rft.pub=Tomash+Publishers&amp;rft.date=1961&amp;rft.isbn=978-0-938228-08-0&amp;rft.aulast=Hawkins&amp;rft.aufirst=David&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fprojectylosalamo0002unse&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHewlettAnderson1962" class="citation book cs1"><a href="/wiki/Richard_G._Hewlett" title="Richard G. Hewlett">Hewlett, Richard G.</a>; Anderson, Oscar E. (1962). <a rel="nofollow" class="external text" href="https://www.governmentattic.org/5docs/TheNewWorld1939-1946.pdf"><i>The New World, 1939–1946</i></a> <span class="cs1-format">(PDF)</span>. University Park: <a href="/wiki/Pennsylvania_State_University_Press" class="mw-redirect" title="Pennsylvania State University Press">Pennsylvania State University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-520-07186-5" title="Special:BookSources/978-0-520-07186-5"><bdi>978-0-520-07186-5</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/637004643">637004643</a>. <a rel="nofollow" class="external text" href="https://ghostarchive.org/archive/20221009/https://www.governmentattic.org/5docs/TheNewWorld1939-1946.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 9 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">26 March</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+New+World%2C+1939%E2%80%931946&amp;rft.place=University+Park&amp;rft.pub=Pennsylvania+State+University+Press&amp;rft.date=1962&amp;rft_id=info%3Aoclcnum%2F637004643&amp;rft.isbn=978-0-520-07186-5&amp;rft.aulast=Hewlett&amp;rft.aufirst=Richard+G.&amp;rft.au=Anderson%2C+Oscar+E.&amp;rft_id=https%3A%2F%2Fwww.governmentattic.org%2F5docs%2FTheNewWorld1939-1946.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHewlettDuncan1969" class="citation book cs1">Hewlett, Richard G.; Duncan, Francis (1969). <a rel="nofollow" class="external text" href="http://energy.gov/sites/prod/files/2013/04/f0/Hewlett%20and%20Duncan%20-%20Atomic%20Shield%20%28complete%29.pdf"><i>Atomic Shield, 1947–1952</i></a> <span class="cs1-format">(PDF)</span>. A History of the United States Atomic Energy Commission. University Park: Pennsylvania State University Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-520-07187-2" title="Special:BookSources/978-0-520-07187-2"><bdi>978-0-520-07187-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/3717478">3717478</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170716200014/https://energy.gov/sites/prod/files/2013/04/f0/Hewlett%20and%20Duncan%20-%20Atomic%20Shield%20%28complete%29.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 16 July 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">13 December</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Atomic+Shield%2C+1947%E2%80%931952&amp;rft.place=University+Park&amp;rft.series=A+History+of+the+United+States+Atomic+Energy+Commission&amp;rft.pub=Pennsylvania+State+University+Press&amp;rft.date=1969&amp;rft_id=info%3Aoclcnum%2F3717478&amp;rft.isbn=978-0-520-07187-2&amp;rft.aulast=Hewlett&amp;rft.aufirst=Richard+G.&amp;rft.au=Duncan%2C+Francis&amp;rft_id=http%3A%2F%2Fenergy.gov%2Fsites%2Fprod%2Ffiles%2F2013%2F04%2Ff0%2FHewlett%2520and%2520Duncan%2520-%2520Atomic%2520Shield%2520%2528complete%2529.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHoddesonHenriksenMeadeWestfall1993" class="citation book cs1"><a href="/wiki/Lillian_Hoddeson" title="Lillian Hoddeson">Hoddeson, Lillian</a>; Henriksen, Paul W.; Meade, Roger A.; <a href="/wiki/Catherine_Westfall" title="Catherine Westfall">Westfall, Catherine L.</a> (1993). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/criticalassembly0000unse"><i>Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943–1945</i></a></span>. New York: Cambridge University Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-521-44132-2" title="Special:BookSources/978-0-521-44132-2"><bdi>978-0-521-44132-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/26764320">26764320</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Critical+Assembly%3A+A+Technical+History+of+Los+Alamos+During+the+Oppenheimer+Years%2C+1943%E2%80%931945&amp;rft.place=New+York&amp;rft.pub=Cambridge+University+Press&amp;rft.date=1993&amp;rft_id=info%3Aoclcnum%2F26764320&amp;rft.isbn=978-0-521-44132-2&amp;rft.aulast=Hoddeson&amp;rft.aufirst=Lillian&amp;rft.au=Henriksen%2C+Paul+W.&amp;rft.au=Meade%2C+Roger+A.&amp;rft.au=Westfall%2C+Catherine+L.&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fcriticalassembly0000unse&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHowesHerzenberg1999" class="citation book cs1"><a href="/wiki/Ruth_Howes" title="Ruth Howes">Howes, Ruth H.</a>; <a href="/wiki/Caroline_Herzenberg" title="Caroline Herzenberg">Herzenberg, Caroline L.</a> (1999). <i>Their Day in the Sun: Women of the Manhattan Project</i>. Philadelphia: <a href="/wiki/Temple_University_Press" title="Temple University Press">Temple University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-1-56639-719-3" title="Special:BookSources/978-1-56639-719-3"><bdi>978-1-56639-719-3</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/49569088">49569088</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Their+Day+in+the+Sun%3A+Women+of+the+Manhattan+Project&amp;rft.place=Philadelphia&amp;rft.pub=Temple+University+Press&amp;rft.date=1999&amp;rft_id=info%3Aoclcnum%2F49569088&amp;rft.isbn=978-1-56639-719-3&amp;rft.aulast=Howes&amp;rft.aufirst=Ruth+H.&amp;rft.au=Herzenberg%2C+Caroline+L.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHunner2004" class="citation book cs1">Hunner, Jon (2004). <i>Inventing Los Alamos: The Growth of an Atomic Community</i>. Norman: <a href="/wiki/University_of_Oklahoma_Press" title="University of Oklahoma Press">University of Oklahoma Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-8061-3891-6" title="Special:BookSources/978-0-8061-3891-6"><bdi>978-0-8061-3891-6</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/154690200">154690200</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Inventing+Los+Alamos%3A+The+Growth+of+an+Atomic+Community&amp;rft.place=Norman&amp;rft.pub=University+of+Oklahoma+Press&amp;rft.date=2004&amp;rft_id=info%3Aoclcnum%2F154690200&amp;rft.isbn=978-0-8061-3891-6&amp;rft.aulast=Hunner&amp;rft.aufirst=Jon&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJones1985" class="citation book cs1">Jones, Vincent (1985). <a rel="nofollow" class="external text" href="https://history.army.mil/html/books/011/11-10/CMH_Pub_11-10.pdf"><i>Manhattan: The Army and the Atomic Bomb</i></a> <span class="cs1-format">(PDF)</span>. Washington, D.C.: United States Army Center of Military History. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/10913875">10913875</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170506150025/http://www.history.army.mil//html/books/011/11-10/CMH_Pub_11-10.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 6 May 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">25 August</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Manhattan%3A+The+Army+and+the+Atomic+Bomb&amp;rft.place=Washington%2C+D.C.&amp;rft.pub=United+States+Army+Center+of+Military+History&amp;rft.date=1985&amp;rft_id=info%3Aoclcnum%2F10913875&amp;rft.aulast=Jones&amp;rft.aufirst=Vincent&amp;rft_id=https%3A%2F%2Fhistory.army.mil%2Fhtml%2Fbooks%2F011%2F11-10%2FCMH_Pub_11-10.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFManhattan_District1947a" class="citation book cs1">Manhattan District (1947a). <a rel="nofollow" class="external text" href="https://www.osti.gov/includes/opennet/includes/MED_scans/Book%20VIII%20-%20%20Volume%201%20-%20Los%20Alamos%20Project%20(Y)%20-%20General.pdf"><i>Manhattan District History, Book VIII, Volume 1 – Los Alamos Project – General</i></a> <span class="cs1-format">(PDF)</span>. Washington, D.C.: Manhattan District. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170212105339/http://www.osti.gov/includes/opennet/includes/MED_scans/Book%20VIII%20-%20%20Volume%201%20-%20Los%20Alamos%20Project%20(Y)%20-%20General.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 12 February 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">7 March</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Manhattan+District+History%2C+Book+VIII%2C+Volume+1+%E2%80%93+Los+Alamos+Project+%E2%80%93+General&amp;rft.place=Washington%2C+D.C.&amp;rft.pub=Manhattan+District&amp;rft.date=1947&amp;rft.au=Manhattan+District&amp;rft_id=http%3A%2F%2Fwww.osti.gov%2Fincludes%2Fopennet%2Fincludes%2FMED_scans%2FBook%2520VIII%2520-%2520%2520Volume%25201%2520-%2520Los%2520Alamos%2520Project%2520%28Y%29%2520-%2520General.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMonk2012" class="citation book cs1"><a href="/wiki/Ray_Monk" title="Ray Monk">Monk, Ray</a> (2012). <i>Robert Oppenheimer: A Life Inside the Center</i>. New York; Toronto: <a href="/wiki/Doubleday_(publisher)" title="Doubleday (publisher)">Doubleday</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-385-50407-2" title="Special:BookSources/978-0-385-50407-2"><bdi>978-0-385-50407-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Robert+Oppenheimer%3A+A+Life+Inside+the+Center&amp;rft.place=New+York%3B+Toronto&amp;rft.pub=Doubleday&amp;rft.date=2012&amp;rft.isbn=978-0-385-50407-2&amp;rft.aulast=Monk&amp;rft.aufirst=Ray&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNichols1987" class="citation book cs1"><a href="/wiki/Kenneth_Nichols" title="Kenneth Nichols">Nichols, Kenneth David</a> (1987). <i>The Road to Trinity: A Personal Account of How America's Nuclear Policies Were Made</i>. New York: William Morrow and Company. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-688-06910-0" title="Special:BookSources/978-0-688-06910-0"><bdi>978-0-688-06910-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/15223648">15223648</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Road+to+Trinity%3A+A+Personal+Account+of+How+America%27s+Nuclear+Policies+Were+Made&amp;rft.place=New+York&amp;rft.pub=William+Morrow+and+Company&amp;rft.date=1987&amp;rft_id=info%3Aoclcnum%2F15223648&amp;rft.isbn=978-0-688-06910-0&amp;rft.aulast=Nichols&amp;rft.aufirst=Kenneth+David&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRamsey2012" class="citation book cs1"><a href="/wiki/Norman_F._Ramsey" class="mw-redirect" title="Norman F. Ramsey">Ramsey, N. F.</a> (2012). "History of Project A". In Coster-Mullen, John (ed.). <i>Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man</i>. United States: J. Coster-Mullen. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/298514167">298514167</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=bookitem&amp;rft.atitle=History+of+Project+A&amp;rft.btitle=Atom+Bombs%3A+The+Top+Secret+Inside+Story+of+Little+Boy+and+Fat+Man&amp;rft.place=United+States&amp;rft.pub=J.+Coster-Mullen&amp;rft.date=2012&amp;rft_id=info%3Aoclcnum%2F298514167&amp;rft.aulast=Ramsey&amp;rft.aufirst=N.+F.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRhodes1986" class="citation book cs1"><a href="/wiki/Richard_Rhodes" title="Richard Rhodes">Rhodes, Richard</a> (1986). <a href="/wiki/The_Making_of_the_Atomic_Bomb" title="The Making of the Atomic Bomb"><i>The Making of the Atomic Bomb</i></a>. New York: Simon &amp; Schuster. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-671-44133-3" title="Special:BookSources/978-0-671-44133-3"><bdi>978-0-671-44133-3</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/13793436">13793436</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Making+of+the+Atomic+Bomb&amp;rft.place=New+York&amp;rft.pub=Simon+%26+Schuster&amp;rft.date=1986&amp;rft_id=info%3Aoclcnum%2F13793436&amp;rft.isbn=978-0-671-44133-3&amp;rft.aulast=Rhodes&amp;rft.aufirst=Richard&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRhodes1995" class="citation book cs1">Rhodes, Richard (1995). <a rel="nofollow" class="external text" href="https://archive.org/details/darksunmakingofh00rhod"><i>Dark Sun: The Making of the Hydrogen Bomb</i></a>. New York: Simon &amp; Schuster. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-684-80400-2" title="Special:BookSources/978-0-684-80400-2"><bdi>978-0-684-80400-2</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Dark+Sun%3A+The+Making+of+the+Hydrogen+Bomb&amp;rft.place=New+York&amp;rft.pub=Simon+%26+Schuster&amp;rft.date=1995&amp;rft.isbn=978-0-684-80400-2&amp;rft.aulast=Rhodes&amp;rft.aufirst=Richard&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fdarksunmakingofh00rhod&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRuss1990" class="citation book cs1">Russ, Harlow W. (1990). <i>Project Alberta: The Preparation of Atomic Bombs For Use in World War II</i>. Los Alamos, New Mexico: Exceptional Books. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-944482-01-8" title="Special:BookSources/978-0-944482-01-8"><bdi>978-0-944482-01-8</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/24429257">24429257</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Project+Alberta%3A+The+Preparation+of+Atomic+Bombs+For+Use+in+World+War+II&amp;rft.place=Los+Alamos%2C+New+Mexico&amp;rft.pub=Exceptional+Books&amp;rft.date=1990&amp;rft_id=info%3Aoclcnum%2F24429257&amp;rft.isbn=978-0-944482-01-8&amp;rft.aulast=Russ&amp;rft.aufirst=Harlow+W.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSerberRhodes1992" class="citation book cs1"><a href="/wiki/Robert_Serber" title="Robert Serber">Serber, Robert</a>; <a href="/wiki/Richard_Rhodes" title="Richard Rhodes">Rhodes, Richard</a> (1992). <a href="/wiki/The_Los_Alamos_Primer" class="mw-redirect" title="The Los Alamos Primer"><i>The Los Alamos Primer: The First Lectures on How to Build an Atomic Bomb</i></a>. Berkeley: University of California Press. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-520-07576-4" title="Special:BookSources/978-0-520-07576-4"><bdi>978-0-520-07576-4</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/23693470">23693470</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Los+Alamos+Primer%3A+The+First+Lectures+on+How+to+Build+an+Atomic+Bomb&amp;rft.place=Berkeley&amp;rft.pub=University+of+California+Press&amp;rft.date=1992&amp;rft_id=info%3Aoclcnum%2F23693470&amp;rft.isbn=978-0-520-07576-4&amp;rft.aulast=Serber&amp;rft.aufirst=Robert&amp;rft.au=Rhodes%2C+Richard&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSerberCrease1998" class="citation book cs1"><a href="/wiki/Robert_Serber" title="Robert Serber">Serber, Robert</a>; Crease, Robert P. (1998). <a rel="nofollow" class="external text" href="https://archive.org/details/peacewarreminisc00serb"><i>Peace &amp; War: Reminiscences of a Life on the Frontiers of Science</i></a>. New York: <a href="/wiki/Columbia_University_Press" title="Columbia University Press">Columbia University Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-231-10546-0" title="Special:BookSources/978-0-231-10546-0"><bdi>978-0-231-10546-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/37631186">37631186</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Peace+%26+War%3A+Reminiscences+of+a+Life+on+the+Frontiers+of+Science&amp;rft.place=New+York&amp;rft.pub=Columbia+University+Press&amp;rft.date=1998&amp;rft_id=info%3Aoclcnum%2F37631186&amp;rft.isbn=978-0-231-10546-0&amp;rft.aulast=Serber&amp;rft.aufirst=Robert&amp;rft.au=Crease%2C+Robert+P.&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fpeacewarreminisc00serb&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSteeper2003" class="citation book cs1">Steeper, Nancy Cook (2003). <i>Gatekeeper to Los Alamos: Dorothy Scarritt McKibbin</i>. Los Alamos: Alamos Historical Society. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-941232-30-2" title="Special:BookSources/978-0-941232-30-2"><bdi>978-0-941232-30-2</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/57475908">57475908</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Gatekeeper+to+Los+Alamos%3A+Dorothy+Scarritt+McKibbin&amp;rft.place=Los+Alamos&amp;rft.pub=Alamos+Historical+Society&amp;rft.date=2003&amp;rft_id=info%3Aoclcnum%2F57475908&amp;rft.isbn=978-0-941232-30-2&amp;rft.aulast=Steeper&amp;rft.aufirst=Nancy+Cook&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSzasz1992" class="citation book cs1">Szasz, Ferenc Morton (1992). <i>British Scientists and the Manhattan Project: the Los Alamos Years</i>. New York: <a href="/wiki/St._Martin%27s_Press" title="St. Martin&#39;s Press">St. Martin's Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-312-06167-8" title="Special:BookSources/978-0-312-06167-8"><bdi>978-0-312-06167-8</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/23901666">23901666</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=British+Scientists+and+the+Manhattan+Project%3A+the+Los+Alamos+Years&amp;rft.place=New+York&amp;rft.pub=St.+Martin%27s+Press&amp;rft.date=1992&amp;rft_id=info%3Aoclcnum%2F23901666&amp;rft.isbn=978-0-312-06167-8&amp;rft.aulast=Szasz&amp;rft.aufirst=Ferenc+Morton&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTruslow1973" class="citation book cs1">Truslow, Edith C. (1973). <a rel="nofollow" class="external text" href="https://www.osti.gov/opennet/manhattan-project-history/publications/LANLMDHNonscientificAspects.pdf"><i>Manhattan District History – Nonscientific aspects of Los Alamos Project Y 1942 though 1946</i></a> <span class="cs1-format">(PDF)</span>. Los Alamos, New Mexico: Los Alamos National Laboratory. LA-5200. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170822211940/https://www.osti.gov/opennet/manhattan-project-history/publications/LANLMDHNonscientificAspects.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 22 August 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">21 August</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Manhattan+District+History+%E2%80%93+Nonscientific+aspects+of+Los+Alamos+Project+Y+1942+though+1946&amp;rft.place=Los+Alamos%2C+New+Mexico&amp;rft.pub=Los+Alamos+National+Laboratory&amp;rft.date=1973&amp;rft.aulast=Truslow&amp;rft.aufirst=Edith+C.&amp;rft_id=https%3A%2F%2Fwww.osti.gov%2Fopennet%2Fmanhattan-project-history%2Fpublications%2FLANLMDHNonscientificAspects.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTruslowSmith1961" class="citation book cs1">Truslow, Edith C.; Smith, Ralph Carlisle (1961). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/projectylosalamo0002unse"><i>Manhattan District History, Project Y, the Los Alamos Project – Volume II: August 1945 Though December 1946</i></a></span>. Los Angeles: Tomash Publishers. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-938228-08-0" title="Special:BookSources/978-0-938228-08-0"><bdi>978-0-938228-08-0</bdi></a>. LAMS-2532<span class="reference-accessdate">. Retrieved <span class="nowrap">20 February</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Manhattan+District+History%2C+Project+Y%2C+the+Los+Alamos+Project+%E2%80%93+Volume+II%3A+August+1945+Though+December+1946&amp;rft.place=Los+Angeles&amp;rft.pub=Tomash+Publishers&amp;rft.date=1961&amp;rft.isbn=978-0-938228-08-0&amp;rft.aulast=Truslow&amp;rft.aufirst=Edith+C.&amp;rft.au=Smith%2C+Ralph+Carlisle&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fprojectylosalamo0002unse&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWarren1966" class="citation book cs1"><a href="/wiki/Stafford_L._Warren" title="Stafford L. Warren">Warren, Stafford L.</a> (1966). "The Role of Radiology in the Development of the Atomic Bomb". In Ahnfeldt, Arnold Lorentz (ed.). <i>Radiology in World War II</i>. Washington, D.C.: Office of the Surgeon General, Department of the Army. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a>&#160;<a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/630225">630225</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=bookitem&amp;rft.atitle=The+Role+of+Radiology+in+the+Development+of+the+Atomic+Bomb&amp;rft.btitle=Radiology+in+World+War+II&amp;rft.place=Washington%2C+D.C.&amp;rft.pub=Office+of+the+Surgeon+General%2C+Department+of+the+Army&amp;rft.date=1966&amp;rft_id=info%3Aoclcnum%2F630225&amp;rft.aulast=Warren&amp;rft.aufirst=Stafford+L.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AProject+Y" class="Z3988"></span></li></ul> </div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Manhattan_Project" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Manhattan_Project" title="Template:Manhattan Project"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Manhattan_Project" title="Template talk:Manhattan Project"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Manhattan_Project" title="Special:EditPage/Template:Manhattan Project"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Manhattan_Project" style="font-size:114%;margin:0 4em"><a href="/wiki/Manhattan_Project" title="Manhattan Project">Manhattan Project</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div><a href="/wiki/Timeline_of_the_Manhattan_Project" title="Timeline of the Manhattan Project">Timeline</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Sites</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ames_Project" title="Ames Project">Ames</a></li> <li><a href="/wiki/Calutron" title="Calutron">Berkeley</a></li> <li><a href="/wiki/Metallurgical_Laboratory" title="Metallurgical Laboratory">Chicago</a> (<a href="/wiki/Site_A" title="Site A">Site A</a>)</li> <li><a href="/wiki/Dayton_Project" title="Dayton Project">Dayton</a></li> <li><a href="/wiki/Hanford_Engineer_Works" title="Hanford Engineer Works">Hanford</a></li> <li><a href="/wiki/Project_Camel" title="Project Camel">Inyokern</a></li> <li><a class="mw-selflink selflink">Los Alamos</a></li> <li><a href="/wiki/Montreal_Laboratory" title="Montreal Laboratory">Montreal</a></li> <li><a href="/wiki/K-25" title="K-25">New York</a></li> <li><a href="/wiki/Clinton_Engineer_Works" title="Clinton Engineer Works">Oak Ridge</a></li> <li><a href="/wiki/Salt_Wells_Pilot_Plant" title="Salt Wells Pilot Plant">Salt Wells Pilot Plant</a></li> <li><a href="/wiki/Trinity_(nuclear_test)" title="Trinity (nuclear test)">Trinity</a></li> <li><a href="/wiki/Wendover_Air_Force_Base" title="Wendover Air Force Base">Wendover</a></li> <li><a href="/wiki/P-9_Project" title="P-9 Project">Heavy water sites</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Administrators</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Vannevar_Bush" title="Vannevar Bush">Vannevar Bush</a></li> <li><a href="/wiki/Arthur_Compton" title="Arthur Compton">Arthur Compton</a></li> <li><a href="/wiki/James_B._Conant" title="James B. Conant">James B. Conant</a></li> <li><a href="/wiki/Priscilla_Duffield" title="Priscilla Duffield">Priscilla Duffield</a></li> <li><a href="/wiki/Thomas_Farrell_(United_States_Army_officer)" title="Thomas Farrell (United States Army officer)">Thomas Farrell</a></li> <li><a href="/wiki/Leslie_Groves" title="Leslie Groves">Leslie Groves</a></li> <li><a href="/wiki/John_Lansdale_Jr." title="John Lansdale Jr.">John Lansdale</a></li> <li><a href="/wiki/Ernest_Lawrence" title="Ernest Lawrence">Ernest Lawrence</a></li> <li><a href="/wiki/James_C._Marshall" title="James C. Marshall">James Marshall</a></li> <li><a href="/wiki/Franklin_Matthias" title="Franklin Matthias">Franklin Matthias</a></li> <li><a href="/wiki/Dorothy_McKibbin" title="Dorothy McKibbin">Dorothy McKibbin</a></li> <li><a href="/wiki/Kenneth_Nichols" title="Kenneth Nichols">Kenneth Nichols</a></li> <li><a href="/wiki/J._Robert_Oppenheimer" title="J. Robert Oppenheimer">Robert Oppenheimer</a></li> <li><a href="/wiki/William_Sterling_Parsons" title="William Sterling Parsons">Deak Parsons</a></li> <li><a href="/wiki/Boris_Pash" title="Boris Pash">Boris Pash</a></li> <li><a href="/wiki/William_R._Purnell" title="William R. Purnell">William Purnell</a></li> <li><a href="/wiki/Frank_Spedding" title="Frank Spedding">Frank Spedding</a></li> <li><a href="/wiki/Charles_Allen_Thomas" title="Charles Allen Thomas">Charles Thomas</a></li> <li><a href="/wiki/Paul_Tibbets" title="Paul Tibbets">Paul Tibbets</a></li> <li><a href="/wiki/William_L._Uanna" title="William L. Uanna">Bud Uanna</a></li> <li><a href="/wiki/Harold_Urey" title="Harold Urey">Harold Urey</a></li> <li><a href="/wiki/Stafford_L._Warren" title="Stafford L. Warren">Stafford Warren</a></li> <li><a href="/wiki/Ed_Westcott" title="Ed Westcott">Ed Westcott</a></li> <li><a href="/wiki/Roscoe_Charles_Wilson" title="Roscoe Charles Wilson">Roscoe Wilson</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Scientists</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Luis_Walter_Alvarez" title="Luis Walter Alvarez">Luis Alvarez</a></li> <li><a href="/wiki/Robert_Bacher" title="Robert Bacher">Robert Bacher</a></li> <li><a href="/wiki/Hans_Bethe" title="Hans Bethe">Hans Bethe</a></li> <li><a href="/wiki/Aage_Bohr" title="Aage Bohr">Aage Bohr</a></li> <li><a href="/wiki/Niels_Bohr" title="Niels Bohr">Niels Bohr</a></li> <li><a href="/wiki/Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a></li> <li><a href="/wiki/James_Chadwick" title="James Chadwick">James Chadwick</a></li> <li><a href="/wiki/John_Cockcroft" title="John Cockcroft">John Cockcroft</a></li> <li><a href="/wiki/Charles_Critchfield" title="Charles Critchfield">Charles Critchfield</a></li> <li><a href="/wiki/Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a></li> <li><a href="/wiki/John_R._Dunning" title="John R. Dunning">John R. Dunning</a></li> <li><a href="/wiki/Enrico_Fermi" title="Enrico Fermi">Enrico Fermi</a></li> <li><a href="/wiki/Richard_Feynman" title="Richard Feynman">Richard Feynman</a></li> <li><a href="/wiki/Val_Logsdon_Fitch" title="Val Logsdon Fitch">Val Fitch</a></li> <li><a href="/wiki/James_Franck" title="James Franck">James Franck</a></li> <li><a href="/wiki/Klaus_Fuchs" title="Klaus Fuchs">Klaus Fuchs</a></li> <li><a href="/wiki/Maria_Goeppert_Mayer" title="Maria Goeppert Mayer">Maria Goeppert Mayer</a></li> <li><a href="/wiki/George_Kistiakowsky" title="George Kistiakowsky">George Kistiakowsky</a></li> <li><a href="/wiki/George_Koval" title="George Koval">George Koval</a></li> <li><a href="/wiki/Willard_Libby" title="Willard Libby">Willard Libby</a></li> <li><a href="/wiki/Edwin_McMillan" title="Edwin McMillan">Edwin McMillan</a></li> <li><a href="/wiki/Mark_Oliphant" title="Mark Oliphant">Mark Oliphant</a></li> <li><a href="/wiki/George_B._Pegram" title="George B. Pegram">George B. Pegram</a></li> <li><a href="/wiki/Norman_Ramsey_Jr." title="Norman Ramsey Jr.">Norman Ramsey Jr.</a></li> <li><a href="/wiki/Isidor_Isaac_Rabi" title="Isidor Isaac Rabi">Isidor Isaac Rabi</a></li> <li><a href="/wiki/James_Rainwater" title="James Rainwater">James Rainwater</a></li> <li><a href="/wiki/Bruno_Rossi" title="Bruno Rossi">Bruno Rossi</a></li> <li><a href="/wiki/Glenn_T._Seaborg" title="Glenn T. Seaborg">Glenn Seaborg</a></li> <li><a href="/wiki/Emilio_Segr%C3%A8" title="Emilio Segrè">Emilio Segrè</a></li> <li><a href="/wiki/Louis_Slotin" title="Louis Slotin">Louis Slotin</a></li> <li><a href="/wiki/Henry_DeWolf_Smyth" title="Henry DeWolf Smyth">Henry DeWolf Smyth</a></li> <li><a href="/wiki/Leo_Szilard" title="Leo Szilard">Leo Szilard</a></li> <li><a href="/wiki/Edward_Teller" title="Edward Teller">Edward Teller</a></li> <li><a href="/wiki/Stanis%C5%82aw_Ulam" title="Stanisław Ulam">Stanisław Ulam</a></li> <li><a href="/wiki/John_von_Neumann" title="John von Neumann">John von Neumann</a></li> <li><a href="/wiki/John_Archibald_Wheeler" title="John Archibald Wheeler">John Wheeler</a></li> <li><a href="/wiki/Eugene_Wigner" title="Eugene Wigner">Eugene Wigner</a></li> <li><a href="/wiki/Robert_R._Wilson" title="Robert R. Wilson">Robert Wilson</a></li> <li><a href="/wiki/Leona_Woods" title="Leona Woods">Leona Woods</a></li> <li><a href="/wiki/Chien-Shiung_Wu" title="Chien-Shiung Wu">Chien-Shiung Wu</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Operations</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alsos_Mission" title="Alsos Mission">Alsos Mission</a></li> <li><a href="/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki" title="Atomic bombings of Hiroshima and Nagasaki">Bombings of Hiroshima and Nagasaki</a></li> <li><a href="/wiki/Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a></li> <li><a href="/wiki/Operation_Peppermint" title="Operation Peppermint">Operation Peppermint</a></li> <li><a href="/wiki/Project_Alberta" title="Project Alberta">Project Alberta</a></li> <li><a href="/wiki/Silverplate" title="Silverplate">Silverplate</a></li> <li><a href="/wiki/509th_Composite_Group" title="509th Composite Group">509th Composite Group</a></li> <li><i><a href="/wiki/Enola_Gay" title="Enola Gay">Enola Gay</a></i></li> <li><i><a href="/wiki/Bockscar" title="Bockscar">Bockscar</a></i></li> <li><i><a href="/wiki/The_Great_Artiste" title="The Great Artiste">The Great Artiste</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Weapons</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fat_Man" title="Fat Man">Fat Man</a></li> <li><a href="/wiki/Little_Boy" title="Little Boy">Little Boy</a></li> <li><a href="/wiki/Pumpkin_bomb" title="Pumpkin bomb">Pumpkin bomb</a></li> <li><a href="/wiki/Thin_Man_(nuclear_bomb)" title="Thin Man (nuclear bomb)">Thin Man</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/African-American_scientists_and_technicians_on_the_Manhattan_Project" title="African-American scientists and technicians on the Manhattan Project">African Americans</a></li> <li><a href="/wiki/Atomic_Energy_Act_of_1946" title="Atomic Energy Act of 1946">Atomic Energy Act of 1946</a></li> <li><a href="/wiki/Bismuth_phosphate_process" title="Bismuth phosphate process">Bismuth phosphate process</a></li> <li><a href="/wiki/British_contribution_to_the_Manhattan_Project" title="British contribution to the Manhattan Project">British contribution</a></li> <li><a href="/wiki/Calutron_Girls" title="Calutron Girls">Calutron Girls</a></li> <li><a href="/wiki/Chicago_Pile-1" title="Chicago Pile-1">Chicago Pile-1</a></li> <li><a href="/wiki/Demon_core" title="Demon core">Demon core</a></li> <li><a href="/wiki/Einstein%E2%80%93Szilard_letter" title="Einstein–Szilard letter">Einstein–Szilard letter</a></li> <li><a href="/wiki/Franck_Report" title="Franck Report">Franck Report</a></li> <li><a href="/wiki/Interim_Committee" title="Interim Committee">Interim Committee</a></li> <li><a href="/wiki/K-25" title="K-25">K-25 Project</a></li> <li><i><a href="/wiki/Los_Alamos_Primer" title="Los Alamos Primer">Los Alamos Primer</a></i></li> <li><a href="/wiki/List_of_Nobel_laureates_who_worked_on_the_Manhattan_Project" title="List of Nobel laureates who worked on the Manhattan Project">Nobel Prize laureates</a></li> <li><a href="/wiki/Oppenheimer_security_hearing" class="mw-redirect" title="Oppenheimer security hearing">Oppenheimer security hearing</a></li> <li><a href="/wiki/Plutonium" title="Plutonium">Plutonium</a></li> <li><a href="/wiki/Quebec_Agreement" title="Quebec Agreement">Quebec Agreement</a></li> <li><a href="/wiki/RaLa_Experiment" title="RaLa Experiment">RaLa Experiment</a></li> <li><a href="/wiki/S-1_Executive_Committee" title="S-1 Executive Committee">S-1 Executive Committee</a></li> <li><a href="/wiki/S-50_(Manhattan_Project)" title="S-50 (Manhattan Project)">S-50 Project</a></li> <li><a href="/wiki/Smyth_Report" title="Smyth Report">Smyth Report</a></li> <li><a href="/wiki/Uranium" title="Uranium">Uranium</a></li> <li><a href="/wiki/X-10_Graphite_Reactor" title="X-10 Graphite Reactor">X-10 Graphite Reactor</a></li> <li><a href="/wiki/Calutron" title="Calutron">Y-12 Project</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Manhattan_Project" title="Category:Manhattan Project">Category</a></div></td></tr></tbody></table></div> <style data-mw-deduplicate="TemplateStyles:r1130092004">.mw-parser-output .portal-bar{font-size:88%;font-weight:bold;display:flex;justify-content:center;align-items:baseline}.mw-parser-output .portal-bar-bordered{padding:0 2em;background-color:#fdfdfd;border:1px solid #a2a9b1;clear:both;margin:1em auto 0}.mw-parser-output .portal-bar-related{font-size:100%;justify-content:flex-start}.mw-parser-output .portal-bar-unbordered{padding:0 1.7em;margin-left:0}.mw-parser-output .portal-bar-header{margin:0 1em 0 0.5em;flex:0 0 auto;min-height:24px}.mw-parser-output .portal-bar-content{display:flex;flex-flow:row wrap;flex:0 1 auto;padding:0.15em 0;column-gap:1em;align-items:baseline;margin:0;list-style:none}.mw-parser-output .portal-bar-content-related{margin:0;list-style:none}.mw-parser-output .portal-bar-item{display:inline-block;margin:0.15em 0.2em;min-height:24px;line-height:24px}@media screen and (max-width:768px){.mw-parser-output .portal-bar{font-size:88%;font-weight:bold;display:flex;flex-flow:column wrap;align-items:baseline}.mw-parser-output .portal-bar-header{text-align:center;flex:0;padding-left:0.5em;margin:0 auto}.mw-parser-output .portal-bar-related{font-size:100%;align-items:flex-start}.mw-parser-output .portal-bar-content{display:flex;flex-flow:row wrap;align-items:center;flex:0;column-gap:1em;border-top:1px solid #a2a9b1;margin:0 auto;list-style:none}.mw-parser-output .portal-bar-content-related{border-top:none;margin:0;list-style:none}}.mw-parser-output .navbox+link+.portal-bar,.mw-parser-output .navbox+style+.portal-bar,.mw-parser-output .navbox+link+.portal-bar-bordered,.mw-parser-output .navbox+style+.portal-bar-bordered,.mw-parser-output .sister-bar+link+.portal-bar,.mw-parser-output .sister-bar+style+.portal-bar,.mw-parser-output .portal-bar+.navbox-styles+.navbox,.mw-parser-output .portal-bar+.navbox-styles+.sister-bar{margin-top:-1px}</style><div class="portal-bar noprint metadata noviewer portal-bar-bordered" role="navigation" aria-label="Portals"><span class="portal-bar-header"><a href="/wiki/Wikipedia:Contents/Portals" title="Wikipedia:Contents/Portals">Portals</a>:</span><ul class="portal-bar-content"><li class="portal-bar-item"><span class="nowrap"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/21px-Radioactive.svg.png" decoding="async" width="21" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/32px-Radioactive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/42px-Radioactive.svg.png 2x" data-file-width="512" data-file-height="446" /></span></span> </span><a href="/wiki/Portal:Nuclear_technology" title="Portal:Nuclear technology">Nuclear technology</a></li><li class="portal-bar-item"><span class="nowrap"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Papapishu-Lab-icon-6.svg/19px-Papapishu-Lab-icon-6.svg.png" decoding="async" width="19" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Papapishu-Lab-icon-6.svg/29px-Papapishu-Lab-icon-6.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ed/Papapishu-Lab-icon-6.svg/38px-Papapishu-Lab-icon-6.svg.png 2x" data-file-width="512" data-file-height="512" /></span></span> </span><a href="/wiki/Portal:Chemistry" title="Portal:Chemistry">Chemistry</a></li><li class="portal-bar-item"><span class="nowrap"><span typeof="mw:File"><a href="/wiki/File:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/17px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png" decoding="async" width="17" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/26px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/34px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 2x" data-file-width="530" data-file-height="600" /></a></span> </span><a href="/wiki/Portal:Physics" title="Portal:Physics">Physics</a></li><li class="portal-bar-item"><span class="nowrap"><span typeof="mw:File"><span><img alt="image" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/17px-Newton%27s_reflecting_telescope.jpg" decoding="async" width="17" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/26px-Newton%27s_reflecting_telescope.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/34px-Newton%27s_reflecting_telescope.jpg 2x" data-file-width="1140" data-file-height="1276" /></span></span> </span><a href="/wiki/Portal:History_of_science" title="Portal:History of science">History of science</a></li></ul></div><style data-mw-deduplicate="TemplateStyles:r1236088147">.mw-parser-output .sister-bar{display:flex;justify-content:center;align-items:baseline;font-size:88%;background-color:#fdfdfd;border:1px solid #a2a9b1;clear:both;margin:1em 0 0;padding:0 2em}.mw-parser-output .sister-bar-header{margin:0 1em 0 0.5em;padding:0.2em 0;flex:0 0 auto;min-height:24px;line-height:22px}.mw-parser-output .sister-bar-content{display:flex;flex-flow:row wrap;flex:0 1 auto;align-items:baseline;padding:0.2em 0;column-gap:1em;margin:0;list-style:none}.mw-parser-output .sister-bar-item{display:flex;align-items:baseline;margin:0.15em 0;min-height:24px;text-align:left}.mw-parser-output .sister-bar-logo{width:22px;line-height:22px;margin:0 0.2em;text-align:right}.mw-parser-output .sister-bar-link{margin:0 0.2em;text-align:left}@media screen and (max-width:960px){.mw-parser-output .sister-bar{flex-flow:column wrap;margin:1em auto 0}.mw-parser-output .sister-bar-header{flex:0 1}.mw-parser-output .sister-bar-content{flex:1;border-top:1px solid #a2a9b1;margin:0;list-style:none}.mw-parser-output .sister-bar-item{flex:0 0 20em;min-width:20em}}.mw-parser-output .navbox+link+.sister-bar,.mw-parser-output .navbox+style+.sister-bar,.mw-parser-output .portal-bar+link+.sister-bar,.mw-parser-output .portal-bar+style+.sister-bar,.mw-parser-output .sister-bar+.navbox-styles+.navbox,.mw-parser-output .sister-bar+.navbox-styles+.portal-bar{margin-top:-1px}@media print{body.ns-0 .mw-parser-output .sister-bar{display:none!important}}</style><div class="noprint metadata sister-bar" role="navigation" aria-label="sister-projects"><div class="sister-bar-header"><b>Project Y</b> at Wikipedia's <a href="/wiki/Wikipedia:Wikimedia_sister_projects" title="Wikipedia:Wikimedia sister projects"><span id="sister-projects" style="white-space:nowrap;">sister projects</span></a>:</div><ul class="sister-bar-content"><li class="sister-bar-item"><span class="sister-bar-logo"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/14px-Commons-logo.svg.png" decoding="async" width="14" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/21px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/28px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></span><span class="sister-bar-link"><b><a href="https://commons.wikimedia.org/wiki/Category:Los_Alamos_National_Laboratory" class="extiw" title="c:Category:Los Alamos National Laboratory">Media</a></b> from Commons</span></li></ul></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox authority-control" aria-labelledby="Authority_control_databases_frameless&amp;#124;text-top&amp;#124;10px&amp;#124;alt=Edit_this_at_Wikidata&amp;#124;link=https&amp;#58;//www.wikidata.org/wiki/Q27832090#identifiers&amp;#124;class=noprint&amp;#124;Edit_this_at_Wikidata" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Authority_control_databases_frameless&amp;#124;text-top&amp;#124;10px&amp;#124;alt=Edit_this_at_Wikidata&amp;#124;link=https&amp;#58;//www.wikidata.org/wiki/Q27832090#identifiers&amp;#124;class=noprint&amp;#124;Edit_this_at_Wikidata" style="font-size:114%;margin:0 4em"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q27832090#identifiers" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">International</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://viaf.org/viaf/183886970">VIAF</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="http://id.worldcat.org/fast/1366402/">FAST</a></span></li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">National</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/n83130576">United States</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="http://olduli.nli.org.il/F/?func=find-b&amp;local_base=NLX10&amp;find_code=UID&amp;request=987007503702705171">Israel</a></span></li></ul></div></td></tr></tbody></table></div> <!-- NewPP limit report Parsed by mw‐web.eqiad.main‐5dc468848‐qxxlk Cached time: 20241122150536 Cache expiry: 2592000 Reduced expiry: false Complications: [vary‐revision‐sha1, show‐toc] CPU time usage: 2.157 seconds Real time usage: 2.575 seconds Preprocessor visited node count: 29808/1000000 Post‐expand include size: 308239/2097152 bytes Template argument size: 33552/2097152 bytes Highest expansion depth: 24/100 Expensive parser function count: 18/500 Unstrip recursion depth: 1/20 Unstrip post‐expand size: 372874/5000000 bytes Lua time usage: 1.262/10.000 seconds Lua memory usage: 12931259/52428800 bytes Lua Profile: MediaWiki\Extension\Scribunto\Engines\LuaSandbox\LuaSandboxCallback::callParserFunction 440 ms 33.3% MediaWiki\Extension\Scribunto\Engines\LuaSandbox\LuaSandboxCallback::getAllExpandedArguments 140 ms 10.6% MediaWiki\Extension\Scribunto\Engines\LuaSandbox\LuaSandboxCallback::getExpandedArgument 120 ms 9.1% ? 120 ms 9.1% MediaWiki\Extension\Scribunto\Engines\LuaSandbox\LuaSandboxCallback::anchorEncode 80 ms 6.1% recursiveClone <mwInit.lua:45> 60 ms 4.5% dataWrapper <mw.lua:672> 60 ms 4.5% MediaWiki\Extension\Scribunto\Engines\LuaSandbox\LuaSandboxCallback::match 40 ms 3.0% format 40 ms 3.0% <mw.lua:694> 20 ms 1.5% [others] 200 ms 15.2% Number of Wikibase entities loaded: 1/400 --> <!-- Transclusion expansion time report (%,ms,calls,template) 100.00% 2195.226 1 -total 34.20% 750.708 302 Template:Sfn 23.13% 507.704 3 Template:Infobox 14.72% 323.125 1 Template:Reflist 12.26% 269.065 1 Template:Infobox_laboratory 8.69% 190.745 1 Template:Infobox_NRHP 8.15% 179.001 40 Template:Cite_book 7.34% 161.170 16 Template:Cite_web 4.91% 107.863 314 Template:Main_other 4.78% 104.833 1 Template:NRISref --> <!-- Saved in parser cache with key enwiki:pcache:idhash:51053117-0!canonical and timestamp 20241122150536 and revision id 1257082060. Rendering was triggered because: page-view --> </div><!--esi <esi:include src="/esitest-fa8a495983347898/content" /> --><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Project_Y&amp;oldid=1257082060">https://en.wikipedia.org/w/index.php?title=Project_Y&amp;oldid=1257082060</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Code_names" title="Category:Code names">Code names</a></li><li><a href="/wiki/Category:Former_nuclear_research_institutes" title="Category:Former nuclear research institutes">Former nuclear research institutes</a></li><li><a href="/wiki/Category:History_of_the_Manhattan_Project" title="Category:History of the Manhattan Project">History of the Manhattan Project</a></li><li><a href="/wiki/Category:Los_Alamos,_New_Mexico" title="Category:Los Alamos, New Mexico">Los Alamos, New Mexico</a></li><li><a href="/wiki/Category:Manhattan_Project_sites" title="Category:Manhattan Project sites">Manhattan Project sites</a></li><li><a href="/wiki/Category:Military_history_of_New_Mexico" title="Category:Military history of New Mexico">Military history of New Mexico</a></li><li><a href="/wiki/Category:Military_in_New_Mexico" title="Category:Military in New Mexico">Military in New Mexico</a></li><li><a href="/wiki/Category:Military_projects_of_the_United_States" title="Category:Military projects of the United States">Military projects of the United States</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Pages_using_gadget_WikiMiniAtlas" title="Category:Pages using gadget WikiMiniAtlas">Pages using gadget WikiMiniAtlas</a></li><li><a href="/wiki/Category:Articles_using_NRISref_without_a_reference_number" title="Category:Articles using NRISref without a reference number">Articles using NRISref without a reference number</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li><li><a href="/wiki/Category:Featured_articles" title="Category:Featured articles">Featured articles</a></li><li><a href="/wiki/Category:Use_dmy_dates_from_October_2019" title="Category:Use dmy dates from October 2019">Use dmy dates from October 2019</a></li><li><a href="/wiki/Category:Coordinates_on_Wikidata" title="Category:Coordinates on Wikidata">Coordinates on Wikidata</a></li><li><a href="/wiki/Category:NRHP_infobox_with_nocat" title="Category:NRHP infobox with nocat">NRHP infobox with nocat</a></li><li><a href="/wiki/Category:Pages_using_multiple_image_with_auto_scaled_images" title="Category:Pages using multiple image with auto scaled images">Pages using multiple image with auto scaled images</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 13 November 2024, at 03:54<span class="anonymous-show">&#160;(UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Project_Y&amp;mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-f69cdc8f6-mkx9z","wgBackendResponseTime":166,"wgPageParseReport":{"limitreport":{"cputime":"2.157","walltime":"2.575","ppvisitednodes":{"value":29808,"limit":1000000},"postexpandincludesize":{"value":308239,"limit":2097152},"templateargumentsize":{"value":33552,"limit":2097152},"expansiondepth":{"value":24,"limit":100},"expensivefunctioncount":{"value":18,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":372874,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 2195.226 1 -total"," 34.20% 750.708 302 Template:Sfn"," 23.13% 507.704 3 Template:Infobox"," 14.72% 323.125 1 Template:Reflist"," 12.26% 269.065 1 Template:Infobox_laboratory"," 8.69% 190.745 1 Template:Infobox_NRHP"," 8.15% 179.001 40 Template:Cite_book"," 7.34% 161.170 16 Template:Cite_web"," 4.91% 107.863 314 Template:Main_other"," 4.78% 104.833 1 Template:NRISref"]},"scribunto":{"limitreport-timeusage":{"value":"1.262","limit":"10.000"},"limitreport-memusage":{"value":12931259,"limit":52428800},"limitreport-logs":"anchor_id_list = table#1 {\n [\"CITEREFAgnewSchreiber1998\"] = 1,\n [\"CITEREFAlvarezTrower1987\"] = 1,\n [\"CITEREFBakerHeckerHarbur1983\"] = 1,\n [\"CITEREFBethe1991\"] = 1,\n [\"CITEREFBohrWheeler1939\"] = 1,\n [\"CITEREFBroad2007\"] = 1,\n [\"CITEREFBunker1983\"] = 1,\n [\"CITEREFCampbell2005\"] = 1,\n [\"CITEREFChambers1999\"] = 1,\n [\"CITEREFChristman1998\"] = 1,\n [\"CITEREFCompton1956\"] = 1,\n [\"CITEREFConant2005\"] = 1,\n [\"CITEREFCoster-Mullen2012\"] = 1,\n [\"CITEREFDash1973\"] = 1,\n [\"CITEREFEbinger2006\"] = 1,\n [\"CITEREFFineRemington1972\"] = 1,\n [\"CITEREFFrisch1979\"] = 1,\n [\"CITEREFGilbert1969\"] = 1,\n [\"CITEREFGowing1964\"] = 1,\n [\"CITEREFGroves1962\"] = 1,\n [\"CITEREFHacker1987\"] = 1,\n [\"CITEREFHahnStrassmann1939\"] = 1,\n [\"CITEREFHansen1995a\"] = 1,\n [\"CITEREFHansen1995b\"] = 1,\n [\"CITEREFHawkins1961\"] = 1,\n [\"CITEREFHewlettAnderson1962\"] = 1,\n [\"CITEREFHewlettDuncan1969\"] = 1,\n [\"CITEREFHoddesonHenriksenMeadeWestfall1993\"] = 1,\n [\"CITEREFHowesHerzenberg1999\"] = 1,\n [\"CITEREFHunner2004\"] = 1,\n [\"CITEREFJones1985\"] = 1,\n [\"CITEREFKonopinskiMarvinTeller1946\"] = 1,\n [\"CITEREFLaurence\"] = 1,\n [\"CITEREFLibby1939\"] = 1,\n [\"CITEREFManhattan_District1947a\"] = 1,\n [\"CITEREFMcLellan\"] = 1,\n [\"CITEREFMeitnerFrisch1939\"] = 1,\n [\"CITEREFMonk2012\"] = 1,\n [\"CITEREFNichols1987\"] = 1,\n [\"CITEREFOliphantShireCrowther1934\"] = 1,\n [\"CITEREFOppenheimer1944\"] = 1,\n [\"CITEREFRamsey2012\"] = 1,\n [\"CITEREFRhodes1986\"] = 1,\n [\"CITEREFRhodes1995\"] = 1,\n [\"CITEREFRuss1990\"] = 1,\n [\"CITEREFScharff-GoldhaberKlaiber1946\"] = 1,\n [\"CITEREFSegrè1952\"] = 1,\n [\"CITEREFSerberCrease1998\"] = 1,\n [\"CITEREFSerberRhodes1992\"] = 1,\n [\"CITEREFSharp1984\"] = 1,\n [\"CITEREFSilvera2023\"] = 1,\n [\"CITEREFSteeper2003\"] = 1,\n [\"CITEREFSzasz1992\"] = 1,\n [\"CITEREFTruslow1973\"] = 1,\n [\"CITEREFTruslowSmith1961\"] = 1,\n [\"CITEREFWarren1966\"] = 1,\n [\"CITEREFWellenstein2015\"] = 1,\n [\"CITEREFWellerstein2016\"] = 1,\n [\"CITEREFYardley2001\"] = 1,\n}\ntemplate_list = table#1 {\n [\"'\"] = 2,\n [\"Authority control\"] = 1,\n [\"Cite book\"] = 40,\n [\"Cite journal\"] = 10,\n [\"Cite news\"] = 5,\n [\"Cite web\"] = 15,\n [\"Convert\"] = 51,\n [\"Coord\"] = 2,\n [\"Featured article\"] = 1,\n [\"Harvnb\"] = 1,\n [\"Inflation\"] = 2,\n [\"Inflation-year\"] = 1,\n [\"Infobox NRHP\"] = 1,\n [\"Infobox laboratory\"] = 1,\n [\"Main\"] = 5,\n [\"Manhattan Project\"] = 1,\n [\"Multiple image\"] = 1,\n [\"NRISref\"] = 1,\n [\"Nuclide\"] = 2,\n [\"Redirect\"] = 1,\n [\"Refbegin\"] = 1,\n [\"Refend\"] = 1,\n [\"Reflist\"] = 1,\n [\"Sfb\"] = 3,\n [\"Sfn\"] = 302,\n [\"Short description\"] = 1,\n [\"Start date\"] = 1,\n [\"SubatomicParticle\"] = 2,\n [\"Subject bar\"] = 1,\n [\"USS\"] = 3,\n [\"Use dmy dates\"] = 1,\n}\narticle_whitelist = table#1 {\n}\n","limitreport-profile":[["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::callParserFunction","440","33.3"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::getAllExpandedArguments","140","10.6"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::getExpandedArgument","120","9.1"],["?","120","9.1"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::anchorEncode","80","6.1"],["recursiveClone \u003CmwInit.lua:45\u003E","60","4.5"],["dataWrapper \u003Cmw.lua:672\u003E","60","4.5"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::match","40","3.0"],["format","40","3.0"],["\u003Cmw.lua:694\u003E","20","1.5"],["[others]","200","15.2"]]},"cachereport":{"origin":"mw-web.eqiad.main-5dc468848-qxxlk","timestamp":"20241122150536","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Project Y","url":"https:\/\/en.wikipedia.org\/wiki\/Project_Y","sameAs":"http:\/\/www.wikidata.org\/entity\/Q27832090","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q27832090","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2016-07-12T02:32:44Z","dateModified":"2024-11-13T03:54:37Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/8\/87\/Army-Navy_E_Award.jpg","headline":"secret laboratory established by the Manhattan Project"}</script> </body> </html>

Pages: 1 2 3 4 5 6 7 8 9 10