CINXE.COM

<!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>Alpha particle - 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":"2ba73a54-cd5b-4bfe-bb81-cdd9a5287d0a","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Alpha_particle","wgTitle":"Alpha particle","wgCurRevisionId":1259190901,"wgRevisionId":1259190901,"wgArticleId":21787470,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Articles with short description","Short description is different from Wikidata","Use dmy dates from September 2024","All articles with unsourced statements","Articles with unsourced statements from February 2023","Pages using multiple image with auto scaled images","Commons category link from Wikidata","Helium","Ionizing radiation","Radioactivity","Subatomic particles with spin 0"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext", "wgRelevantPageName":"Alpha_particle","wgRelevantArticleId":21787470,"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":30000,"wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q103517","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","ext.math.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","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp", "ext.gadget.ReferenceTooltips","ext.gadget.switcher","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&modules=ext.cite.styles%7Cext.math.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&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&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/7/79/Alpha_Decay.svg/1200px-Alpha_Decay.svg.png"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="816"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/7/79/Alpha_Decay.svg/800px-Alpha_Decay.svg.png"> <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/7/79/Alpha_Decay.svg/640px-Alpha_Decay.svg.png"> <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="Alpha particle - 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/Alpha_particle"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Alpha_particle&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/Alpha_particle"> <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&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-Alpha_particle rootpage-Alpha_particle 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'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&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&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&returnto=Alpha+particle" 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&returnto=Alpha+particle" title="You're encouraged to log in; however, it'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&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&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&returnto=Alpha+particle" 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&returnto=Alpha+particle" title="You're encouraged to log in; however, it'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"></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-Name" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Name"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Name</span> </div> </a> <ul id="toc-Name-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Sources" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Sources"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Sources</span> </div> </a> <button aria-controls="toc-Sources-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 Sources subsection</span> </button> <ul id="toc-Sources-sublist" class="vector-toc-list"> <li id="toc-Alpha_decay" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Alpha_decay"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Alpha decay</span> </div> </a> <ul id="toc-Alpha_decay-sublist" class="vector-toc-list"> <li id="toc-Mechanism_of_production_in_alpha_decay" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Mechanism_of_production_in_alpha_decay"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.1</span> <span>Mechanism of production in alpha decay</span> </div> </a> <ul id="toc-Mechanism_of_production_in_alpha_decay-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Ternary_fission" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ternary_fission"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Ternary fission</span> </div> </a> <ul id="toc-Ternary_fission-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Accelerators" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Accelerators"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Accelerators</span> </div> </a> <ul id="toc-Accelerators-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Solar_core_reactions" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Solar_core_reactions"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4</span> <span>Solar core reactions</span> </div> </a> <ul id="toc-Solar_core_reactions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cosmic_rays" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Cosmic_rays"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5</span> <span>Cosmic rays</span> </div> </a> <ul id="toc-Cosmic_rays-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Energy_and_absorption" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Energy_and_absorption"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Energy and absorption</span> </div> </a> <ul id="toc-Energy_and_absorption-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Biological_effects" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Biological_effects"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Biological effects</span> </div> </a> <ul id="toc-Biological_effects-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History_of_discovery_and_use" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#History_of_discovery_and_use"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>History of discovery and use</span> </div> </a> <ul id="toc-History_of_discovery_and_use-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Anti-alpha_particle" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Anti-alpha_particle"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Anti-alpha particle</span> </div> </a> <ul id="toc-Anti-alpha_particle-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Applications" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Applications</span> </div> </a> <button aria-controls="toc-Applications-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 Applications subsection</span> </button> <ul id="toc-Applications-sublist" class="vector-toc-list"> <li id="toc-Devices" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Devices"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.1</span> <span>Devices</span> </div> </a> <ul id="toc-Devices-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cancer_treatment" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Cancer_treatment"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.2</span> <span>Cancer treatment</span> </div> </a> <ul id="toc-Cancer_treatment-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Alpha_radiation_and_DRAM_errors" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Alpha_radiation_and_DRAM_errors"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Alpha radiation and DRAM errors</span> </div> </a> <ul id="toc-Alpha_radiation_and_DRAM_errors-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>See also</span> </div> </a> <ul id="toc-See_also-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">10</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Further_reading" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Further_reading"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>Further reading</span> </div> </a> <ul id="toc-Further_reading-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>External links</span> </div> </a> <ul id="toc-External_links-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">Alpha particle</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 74 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-74" 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">74 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Alfadeeltjie" title="Alfadeeltjie – Afrikaans" lang="af" hreflang="af" data-title="Alfadeeltjie" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%AC%D8%B3%D9%8A%D9%85_%D8%A3%D9%84%D9%81%D8%A7" title="جسيم ألفا – Arabic" lang="ar" hreflang="ar" data-title="جسيم ألفا" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Part%C3%ADcula_alfa" title="Partícula alfa – Asturian" lang="ast" hreflang="ast" data-title="Partícula alfa" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Alfa_hiss%C9%99ciyi" title="Alfa hissəciyi – Azerbaijani" lang="az" hreflang="az" data-title="Alfa hissəciyi" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%86%E0%A6%B2%E0%A6%AB%E0%A6%BE_%E0%A6%95%E0%A6%A3%E0%A6%BE" title="আলফা কণা – Bangla" lang="bn" hreflang="bn" data-title="আলফা কণা" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%90%D0%BB%D1%8C%D1%84%D0%B0-%D1%87%D0%B0%D1%81%D1%86%D1%96%D1%86%D0%B0" title="Альфа-часціца – Belarusian" lang="be" hreflang="be" data-title="Альфа-часціца" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%90%D0%BB%D1%8C%D1%84%D0%B0-%D1%87%D0%B0%D1%81%D1%8C%D1%86%D1%96%D0%BD%D0%BA%D0%B0" title="Альфа-часьцінка – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Альфа-часьцінка" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%90%D0%BB%D1%84%D0%B0-%D1%87%D0%B0%D1%81%D1%82%D0%B8%D1%86%D0%B0" title="Алфа-частица – Bulgarian" lang="bg" hreflang="bg" data-title="Алфа-частица" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%A8%E0%BD%A3%E0%BC%8B%E0%BD%95%E0%BC%8B%E0%BD%A2%E0%BE%A1%E0%BD%B4%E0%BD%A3%E0%BC%8D" title="ཨལ་ཕ་རྡུལ། – Tibetan" lang="bo" hreflang="bo" data-title="ཨལ་ཕ་རྡུལ།" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Alfa_%C4%8Destica" title="Alfa čestica – Bosnian" lang="bs" hreflang="bs" data-title="Alfa čestica" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Part%C3%ADcula_%CE%B1" title="Partícula α – Catalan" lang="ca" hreflang="ca" data-title="Partícula α" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%90%D0%BB%D1%8C%D1%84%D0%B0-%D0%BF%C4%95%D1%80%D1%87%C4%95" title="Альфа-пĕрчĕ – Chuvash" lang="cv" hreflang="cv" data-title="Альфа-пĕрчĕ" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/%C4%8C%C3%A1stice_alfa" title="Částice alfa – Czech" lang="cs" hreflang="cs" data-title="Částice alfa" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da badge-Q70894304 mw-list-item" title=""><a href="https://da.wikipedia.org/wiki/Alfapartikel" title="Alfapartikel – Danish" lang="da" hreflang="da" data-title="Alfapartikel" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-ary mw-list-item"><a href="https://ary.wikipedia.org/wiki/%D9%81%D8%B1%D8%AA%D9%8A%D8%AA%D8%A9_%D8%A3%D9%84%D9%81%D8%A7" title="فرتيتة ألفا – Moroccan Arabic" lang="ary" hreflang="ary" data-title="فرتيتة ألفا" data-language-autonym="الدارجة" data-language-local-name="Moroccan Arabic" class="interlanguage-link-target"><span>الدارجة</span></a></li><li class="interlanguage-link interwiki-de badge-Q70894304 mw-list-item" title=""><a href="https://de.wikipedia.org/wiki/Alphateilchen" title="Alphateilchen – German" lang="de" hreflang="de" data-title="Alphateilchen" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Alfaosake" title="Alfaosake – Estonian" lang="et" hreflang="et" data-title="Alfaosake" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A3%CF%89%CE%BC%CE%B1%CF%84%CE%AF%CE%B4%CE%B9%CE%BF_%CE%AC%CE%BB%CF%86%CE%B1" title="Σωματίδιο άλφα – Greek" lang="el" hreflang="el" data-title="Σωματίδιο άλφα" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Part%C3%ADcula_alfa" title="Partícula alfa – Spanish" lang="es" hreflang="es" data-title="Partícula alfa" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo badge-Q70893996 mw-list-item" title=""><a href="https://eo.wikipedia.org/wiki/Alfa-partiklo" title="Alfa-partiklo – Esperanto" lang="eo" hreflang="eo" data-title="Alfa-partiklo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Alfa_partikula" title="Alfa partikula – Basque" lang="eu" hreflang="eu" data-title="Alfa partikula" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B0%D8%B1%D8%A7%D8%AA_%D8%A2%D9%84%D9%81%D8%A7" title="ذرات آلفا – Persian" lang="fa" hreflang="fa" data-title="ذرات آلفا" 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/Particule_%CE%B1" title="Particule α – French" lang="fr" hreflang="fr" data-title="Particule α" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Alfa-ch%C3%A1ithn%C3%ADn" title="Alfa-cháithnín – Irish" lang="ga" hreflang="ga" data-title="Alfa-cháithnín" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Part%C3%ADcula_alfa" title="Partícula alfa – Galician" lang="gl" hreflang="gl" data-title="Partícula alfa" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%95%8C%ED%8C%8C_%EC%9E%85%EC%9E%90" title="알파 입자 – Korean" lang="ko" hreflang="ko" data-title="알파 입자" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%B1%D5%AC%D6%86%D5%A1-%D5%B4%D5%A1%D5%BD%D5%B6%D5%AB%D5%AF" title="Ալֆա-մասնիկ – Armenian" lang="hy" hreflang="hy" data-title="Ալֆա-մասնիկ" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%85%E0%A4%B2%E0%A5%8D%E0%A4%AB%E0%A4%BE_%E0%A4%95%E0%A4%A3" title="अल्फा कण – Hindi" lang="hi" hreflang="hi" data-title="अल्फा कण" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Alfa-%C4%8Destica" title="Alfa-čestica – Croatian" lang="hr" hreflang="hr" data-title="Alfa-čestica" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Partikel_Alfa" title="Partikel Alfa – Indonesian" lang="id" hreflang="id" data-title="Partikel Alfa" 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-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Particella_%CE%B1" title="Particella α – Italian" lang="it" hreflang="it" data-title="Particella α" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he badge-Q70893996 mw-list-item" title=""><a href="https://he.wikipedia.org/wiki/%D7%97%D7%9C%D7%A7%D7%99%D7%A7_%D7%90%D7%9C%D7%A4%D7%90" title="חלקיק אלפא – Hebrew" lang="he" hreflang="he" data-title="חלקיק אלפא" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%85%E0%B2%B2%E0%B3%8D%E0%B2%AB_%E0%B2%95%E0%B2%A3" title="ಅಲ್ಫ ಕಣ – Kannada" lang="kn" hreflang="kn" data-title="ಅಲ್ಫ ಕಣ" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%90%E1%83%9A%E1%83%A4%E1%83%90-%E1%83%9C%E1%83%90%E1%83%AC%E1%83%98%E1%83%9A%E1%83%90%E1%83%99%E1%83%98" title="ალფა-ნაწილაკი – Georgian" lang="ka" hreflang="ka" data-title="ალფა-ნაწილაკი" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%90%D0%BB%D1%8C%D1%84%D0%B0-%D0%B1%D3%A9%D0%BB%D1%88%D0%B5%D0%BA" title="Альфа-бөлшек – Kazakh" lang="kk" hreflang="kk" data-title="Альфа-бөлшек" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Patikil_alfa" title="Patikil alfa – Haitian Creole" lang="ht" hreflang="ht" data-title="Patikil alfa" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/T%C3%AEr%C3%AAj%C3%AAn_alfay%C3%AA" title="Tîrêjên alfayê – Kurdish" lang="ku" hreflang="ku" data-title="Tîrêjên alfayê" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Alfa_da%C4%BCi%C5%86a" title="Alfa daļiņa – Latvian" lang="lv" hreflang="lv" data-title="Alfa daļiņa" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Alfa_dalel%C4%97" title="Alfa dalelė – Lithuanian" lang="lt" hreflang="lt" data-title="Alfa dalelė" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lij mw-list-item"><a href="https://lij.wikipedia.org/wiki/Raggi_alfa" title="Raggi alfa – Ligurian" lang="lij" hreflang="lij" data-title="Raggi alfa" data-language-autonym="Ligure" data-language-local-name="Ligurian" class="interlanguage-link-target"><span>Ligure</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%90%D0%BB%D1%84%D0%B0-%D1%87%D0%B5%D1%81%D1%82%D0%B8%D1%87%D0%BA%D0%B0" title="Алфа-честичка – Macedonian" lang="mk" hreflang="mk" data-title="Алфа-честичка" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%86%E0%B5%BD%E0%B4%AB%E0%B4%BE_%E0%B4%95%E0%B4%A3%E0%B4%82" title="ആൽഫാ കണം – Malayalam" lang="ml" hreflang="ml" data-title="ആൽഫാ കണം" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Zarah_alfa" title="Zarah alfa – Malay" lang="ms" hreflang="ms" data-title="Zarah alfa" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-my mw-list-item"><a href="https://my.wikipedia.org/wiki/%E1%80%A1%E1%80%9A%E1%80%BA%E1%80%9C%E1%80%BA%E1%80%96%E1%80%AC%E1%80%A1%E1%80%99%E1%80%BE%E1%80%AF%E1%80%94%E1%80%BA" title="အယ်လ်ဖာအမှုန် – Burmese" lang="my" hreflang="my" data-title="အယ်လ်ဖာအမှုန်" data-language-autonym="မြန်မာဘာသာ" data-language-local-name="Burmese" class="interlanguage-link-target"><span>မြန်မာဘာသာ</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Alfadeeltje" title="Alfadeeltje – Dutch" lang="nl" hreflang="nl" data-title="Alfadeeltje" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%A2%E3%83%AB%E3%83%95%E3%82%A1%E7%B2%92%E5%AD%90" title="アルファ粒子 – Japanese" lang="ja" hreflang="ja" data-title="アルファ粒子" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Alfapartikkel" title="Alfapartikkel – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Alfapartikkel" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Alfapartikkel" title="Alfapartikkel – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Alfapartikkel" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Alfa-zarralar" title="Alfa-zarralar – Uzbek" lang="uz" hreflang="uz" data-title="Alfa-zarralar" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%85%E0%A8%B2%E0%A8%AB%E0%A8%BE_%E0%A8%95%E0%A8%A3" title="ਅਲਫਾ ਕਣ – Punjabi" lang="pa" hreflang="pa" data-title="ਅਲਫਾ ਕਣ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%D8%A7%DB%8C%D9%84%D9%81%D8%A7_%D9%BE%D8%A7%D8%B1%D9%B9%DB%8C%DA%A9%D9%84" title="ایلفا پارٹیکل – Western Punjabi" lang="pnb" hreflang="pnb" data-title="ایلفا پارٹیکل" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-nds badge-Q70894304 mw-list-item" title=""><a href="https://nds.wikipedia.org/wiki/Alphadeelken" title="Alphadeelken – Low German" lang="nds" hreflang="nds" data-title="Alphadeelken" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl badge-Q70894304 mw-list-item" title=""><a href="https://pl.wikipedia.org/wiki/Cz%C4%85stka_alfa" title="Cząstka alfa – Polish" lang="pl" hreflang="pl" data-title="Cząstka alfa" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Part%C3%ADcula_alfa" title="Partícula alfa – Portuguese" lang="pt" hreflang="pt" data-title="Partícula alfa" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Particul%C4%83_alfa" title="Particulă alfa – Romanian" lang="ro" hreflang="ro" data-title="Particulă alfa" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%90%D0%BB%D1%8C%D1%84%D0%B0-%D1%87%D0%B0%D1%81%D1%82%D0%B8%D1%86%D0%B0" title="Альфа-частица – Russian" lang="ru" hreflang="ru" data-title="Альфа-частица" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%87%E0%B6%BD%E0%B7%8A%E0%B7%86%E0%B7%8F_%E0%B6%85%E0%B6%82%E0%B7%81%E0%B7%94%E0%B7%80" title="ඇල්ෆා අංශුව – Sinhala" lang="si" hreflang="si" data-title="ඇල්ෆා අංශුව" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Alpha_particle" title="Alpha particle – Simple English" lang="en-simple" hreflang="en-simple" data-title="Alpha particle" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/%C4%8Castica_alfa" title="Častica alfa – Slovak" lang="sk" hreflang="sk" data-title="Častica alfa" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Delec_alfa" title="Delec alfa – Slovenian" lang="sl" hreflang="sl" data-title="Delec alfa" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D8%AA%DB%95%D9%86%DB%86%DA%A9%DB%95%DB%8C_%D8%A6%DB%95%D9%84%D9%81%D8%A7" title="تەنۆکەی ئەلفا – Central Kurdish" lang="ckb" hreflang="ckb" data-title="تەنۆکەی ئەلفا" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Alfa_%C4%8Destica" title="Alfa čestica – Serbian" lang="sr" hreflang="sr" data-title="Alfa čestica" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Alfa-%C4%8Destica" title="Alfa-čestica – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Alfa-čestica" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Alfahiukkanen" title="Alfahiukkanen – Finnish" lang="fi" hreflang="fi" data-title="Alfahiukkanen" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Alfastr%C3%A5lning" title="Alfastrålning – Swedish" lang="sv" hreflang="sv" data-title="Alfastrålning" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%86%E0%AE%B2%E0%AF%8D%E0%AE%83%E0%AE%AA%E0%AE%BE_%E0%AE%A4%E0%AF%81%E0%AE%95%E0%AE%B3%E0%AF%8D" title="ஆல்ஃபா துகள் – Tamil" lang="ta" hreflang="ta" data-title="ஆல்ஃபா துகள்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%AD%E0%B8%99%E0%B8%B8%E0%B8%A0%E0%B8%B2%E0%B8%84%E0%B9%81%E0%B8%AD%E0%B8%A5%E0%B8%9F%E0%B8%B2" title="อนุภาคแอลฟา – Thai" lang="th" hreflang="th" data-title="อนุภาคแอลฟา" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Alfa_par%C3%A7ac%C4%B1%C4%9F%C4%B1" title="Alfa parçacığı – Turkish" lang="tr" hreflang="tr" data-title="Alfa parçacığı" 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%90%D0%BB%D1%8C%D1%84%D0%B0-%D1%87%D0%B0%D1%81%D1%82%D0%B8%D0%BD%D0%BA%D0%B0" title="Альфа-частинка – Ukrainian" lang="uk" hreflang="uk" data-title="Альфа-частинка" 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/H%E1%BA%A1t_alpha" title="Hạt alpha – Vietnamese" lang="vi" hreflang="vi" data-title="Hạt alpha" 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-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Partikulo_Alpha" title="Partikulo Alpha – Waray" lang="war" hreflang="war" data-title="Partikulo Alpha" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%CE%91%E7%B2%92%E5%AD%90" title="Α粒子 – Wu" lang="wuu" hreflang="wuu" data-title="Α粒子" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E7%94%B2%E7%A8%AE%E5%B0%84%E7%B6%AB" title="甲種射綫 – Cantonese" lang="yue" hreflang="yue" data-title="甲種射綫" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%CE%91%E7%B2%92%E5%AD%90" title="Α粒子 – Chinese" lang="zh" hreflang="zh" data-title="Α粒子" 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/Q103517#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/Alpha_particle" 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:Alpha_particle" 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/Alpha_particle"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Alpha_particle&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=Alpha_particle&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/Alpha_particle"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Alpha_particle&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=Alpha_particle&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/Alpha_particle" 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/Alpha_particle" 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=Alpha_particle&oldid=1259190901" 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=Alpha_particle&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&page=Alpha_particle&id=1259190901&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&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAlpha_particle"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FAlpha_particle"><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&page=Alpha_particle&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=Alpha_particle&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/Alpha_particle" 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/Q103517" 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> <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">Ionizing radiation particle of two protons and two neutrons</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"><caption class="infobox-title">Alpha particle</caption><tbody><tr><td colspan="2" class="infobox-image"><figure class="mw-halign-center" typeof="mw:File"><a href="/wiki/File:Alpha_Decay.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/79/Alpha_Decay.svg/250px-Alpha_Decay.svg.png" decoding="async" width="250" height="170" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/79/Alpha_Decay.svg/375px-Alpha_Decay.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/79/Alpha_Decay.svg/500px-Alpha_Decay.svg.png 2x" data-file-width="250" data-file-height="170" /></a><figcaption></figcaption></figure><div class="infobox-caption"><a href="/wiki/Alpha_decay" title="Alpha decay">Alpha decay</a></div></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Particle#Composition" title="Particle">Composition</a></th><td class="infobox-data">2 protons, 2 neutrons</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Particle_statistics" title="Particle statistics">Statistics</a></th><td class="infobox-data"><a href="/wiki/Boson" title="Boson">Bosonic</a></td></tr><tr><th scope="row" class="infobox-label">Symbol</th><td class="infobox-data">α, α<sup>2+</sup>, He<sup>2+</sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Invariant_mass" title="Invariant mass">Mass</a></th><td class="infobox-data"><span class="nowrap"><span data-sort-value="6973664465734500000♠"></span>6.644<span style="margin-left:.25em;">657</span><span style="margin-left:.25em;">3450</span>(21)<span style="margin-left:0.25em;margin-right:0.15em;">×</span>10<sup>−27</sup> kg</span><span style="visibility:hidden; color:transparent; padding-left:2px">‍</span><sup id="cite_ref-physconst-malpha_1-0" class="reference"><a href="#cite_note-physconst-malpha-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><br /><span class="nowrap"><span data-sort-value="7000400150617912899♠"></span>4.001<span style="margin-left:.25em;">506</span><span style="margin-left:.25em;">179</span><span style="margin-left:.25em;">129</span>(62) Da</span><span style="visibility:hidden; color:transparent; padding-left:2px">‍</span><sup id="cite_ref-physconst-malphaDa_2-0" class="reference"><a href="#cite_note-physconst-malphaDa-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><br /><span class="nowrap"><span data-sort-value="7000372737941180000♠"></span>3.727<span style="margin-left:.25em;">379</span><span style="margin-left:.25em;">4118</span>(11)</span> <span class="nowrap"><a href="/wiki/Electronvolt#Mass" title="Electronvolt">GeV/<i>c</i><sup>2</sup></a></span><sup id="cite_ref-physconst-malphac2GeV_3-0" class="reference"><a href="#cite_note-physconst-malphac2GeV-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Electric_charge" title="Electric charge">Electric charge</a></th><td class="infobox-data">+2 <a href="/wiki/Elementary_charge" title="Elementary charge"><i>e</i></a></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Spin_(physics)" title="Spin (physics)">Spin</a></th><td class="infobox-data">0 <a href="/wiki/Reduced_Planck_constant" class="mw-redirect" title="Reduced Planck constant"><i>ħ</i></a><sup id="cite_ref-Krane_4-0" class="reference"><a href="#cite_note-Krane-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></td></tr></tbody></table> <p><b>Alpha particles</b>, also called <b>alpha rays</b> or <b>alpha radiation</b>, consist of two <a href="/wiki/Proton" title="Proton">protons</a> and two <a href="/wiki/Neutron" title="Neutron">neutrons</a> bound together into a <a href="/wiki/Particle" title="Particle">particle</a> identical to a <a href="/wiki/Helium-4" title="Helium-4">helium-4</a> <a href="/wiki/Atomic_nucleus" title="Atomic nucleus">nucleus</a>.<sup id="cite_ref-:02_5-0" class="reference"><a href="#cite_note-:02-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> They are generally produced in the process of <a href="/wiki/Alpha_decay" title="Alpha decay">alpha decay</a> but may also be produced in other ways. Alpha particles are named after the first letter in the <a href="/wiki/Greek_alphabet" title="Greek alphabet">Greek alphabet</a>, <a href="/wiki/Alpha" title="Alpha">α</a>. The symbol for the alpha particle is α or α<sup>2+</sup>. Because they are identical to helium nuclei, they are also sometimes written as He<sup>2+</sup> or <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He</span><sup>2+</sup> indicating a helium <a href="/wiki/Ion" title="Ion">ion</a> with a +2 charge (missing its two <a href="/wiki/Electron" title="Electron">electrons</a>). Once the ion gains electrons from its environment, the alpha particle becomes a normal (electrically neutral) helium atom <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He</span>. </p><p>Alpha particles have a net spin of zero. When produced in standard alpha <a href="/wiki/Radioactive_decay" title="Radioactive decay">radioactive decay</a>, alpha particles generally have a <a href="/wiki/Kinetic_energy" title="Kinetic energy">kinetic energy</a> of about 5 <a href="/wiki/MeV" class="mw-redirect" title="MeV">MeV</a> and a <a href="/wiki/Velocity" title="Velocity">velocity</a> in the vicinity of 4% of the <a href="/wiki/Speed_of_light" title="Speed of light">speed of light</a>. They are a highly <a href="/wiki/Ionizing_radiation" title="Ionizing radiation">ionizing</a> form of <a href="/wiki/Particle_radiation" title="Particle radiation">particle radiation</a>, with low <a href="/wiki/Penetration_depth" title="Penetration depth">penetration depth</a> (stopped by a few centimetres of <a href="/wiki/Air" class="mw-redirect" title="Air">air</a>, or by the <a href="/wiki/Skin" title="Skin">skin</a>). </p><p>However, so-called <a href="/wiki/Long-range_alpha" class="mw-redirect" title="Long-range alpha">long-range alpha</a> particles from <a href="/wiki/Ternary_fission" title="Ternary fission">ternary fission</a> are three times as energetic and penetrate three times as far. The helium nuclei that form 10–12% of <a href="/wiki/Cosmic_ray" title="Cosmic ray">cosmic rays</a> are also usually of much higher energy than those produced by nuclear decay processes, and thus may be highly penetrating and able to traverse the human body and also many metres of dense solid shielding, depending on their energy. To a lesser extent, this is also true of very high-energy helium nuclei produced by particle accelerators. </p> <style data-mw-deduplicate="TemplateStyles:r886046785">.mw-parser-output .toclimit-2 .toclevel-1 ul,.mw-parser-output .toclimit-3 .toclevel-2 ul,.mw-parser-output .toclimit-4 .toclevel-3 ul,.mw-parser-output .toclimit-5 .toclevel-4 ul,.mw-parser-output .toclimit-6 .toclevel-5 ul,.mw-parser-output .toclimit-7 .toclevel-6 ul{display:none}</style><div class="toclimit-3"><meta property="mw:PageProp/toc" /></div> <div class="mw-heading mw-heading2"><h2 id="Name">Name</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=1" title="Edit section: Name"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The term "alpha particle" was coined by <a href="/wiki/Ernest_Rutherford" title="Ernest Rutherford">Ernest Rutherford</a> in reporting his studies of the properties of uranium radiation.<sup id="cite_ref-RutherfordAlpha_6-0" class="reference"><a href="#cite_note-RutherfordAlpha-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The radiation appeared to have two different characters, the first he called "<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \alpha }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>α</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \alpha }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b79333175c8b3f0840bfb4ec41b8072c83ea88d3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.488ex; height:1.676ex;" alt="{\displaystyle \alpha }"></span> radiation" and the more penetrating one he called "<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \beta }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>β</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \beta }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/7ed48a5e36207156fb792fa79d29925d2f7901e8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:1.332ex; height:2.509ex;" alt="{\displaystyle \beta }"></span> radiation". After five years of additional experimental work, Rutherford and <a href="/wiki/Hans_Geiger" title="Hans Geiger">Hans Geiger</a> determined that "the alpha particle, after it has lost its positive charge, is a Helium atom".<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-PaisInward_9-0" class="reference"><a href="#cite_note-PaisInward-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 61">: 61 </span></sup> Alpha radiation consists of particles equivalent to <i>doubly-ionized helium nuclei</i> (He<sup>2+</sup>) which can gain electrons from passing through matter. This mechanism is the origin of terrestrial helium gas.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Sources">Sources</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=2" title="Edit section: Sources"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Alpha_decay">Alpha decay</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=3" title="Edit section: Alpha decay"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></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">Main article: <a href="/wiki/Alpha_decay" title="Alpha decay">Alpha decay</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg/310px-Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg" decoding="async" width="310" height="248" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg/465px-Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg/620px-Physicist_Studying_Alpha_Rays_GPN-2000-000381.jpg 2x" data-file-width="3000" data-file-height="2400" /></a><figcaption>A physicist observes alpha particles from the decay of a polonium source in a <a href="/wiki/Cloud_chamber" title="Cloud chamber">cloud chamber</a></figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Alpha_radiation_in_a_cloud_chamber.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/27/Alpha_radiation_in_a_cloud_chamber.jpg/310px-Alpha_radiation_in_a_cloud_chamber.jpg" decoding="async" width="310" height="174" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/27/Alpha_radiation_in_a_cloud_chamber.jpg/465px-Alpha_radiation_in_a_cloud_chamber.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/27/Alpha_radiation_in_a_cloud_chamber.jpg/620px-Alpha_radiation_in_a_cloud_chamber.jpg 2x" data-file-width="1920" data-file-height="1080" /></a><figcaption>Alpha radiation detected in an isopropanol <a href="/wiki/Cloud_chamber" title="Cloud chamber">cloud chamber</a> (after injection of an artificial source radon-220)</figcaption></figure> <p>The best-known source of alpha particles is <a href="/wiki/Alpha_decay" title="Alpha decay">alpha decay</a> of heavier (mass number of at least 104) atoms. When an <a href="/wiki/Atom" title="Atom">atom</a> emits an alpha particle in alpha decay, the atom's <a href="/wiki/Mass_number" title="Mass number">mass number</a> decreases by four due to the loss of the four <a href="/wiki/Nucleon" title="Nucleon">nucleons</a> in the alpha particle. The <a href="/wiki/Atomic_number" title="Atomic number">atomic number</a> of the atom goes down by two, as a result of the loss of two protons – the atom becomes a new element. Examples of this sort of <a href="/wiki/Nuclear_transmutation" title="Nuclear transmutation">nuclear transmutation</a> by alpha decay are the decay of <a href="/wiki/Uranium" title="Uranium">uranium</a> to <a href="/wiki/Thorium" title="Thorium">thorium</a>, and that of <a href="/wiki/Radium" title="Radium">radium</a> to <a href="/wiki/Radon" title="Radon">radon</a>. </p><p>Alpha particles are commonly emitted by all of the larger <a href="/wiki/Radioactive" class="mw-redirect" title="Radioactive">radioactive</a> nuclei such as <a href="/wiki/Uranium" title="Uranium">uranium</a>, <a href="/wiki/Thorium" title="Thorium">thorium</a>, <a href="/wiki/Actinium" title="Actinium">actinium</a>, and <a href="/wiki/Radium" title="Radium">radium</a>, as well as the <a href="/wiki/Transuranic" class="mw-redirect" title="Transuranic">transuranic</a> elements. Unlike other types of decay, alpha decay as a process must have a minimum-size atomic nucleus that can support it. The smallest nuclei that have to date been found to be capable of alpha emission are <a href="/wiki/Beryllium-8" title="Beryllium-8">beryllium-8</a> and <a href="/wiki/Tellurium-104" class="mw-redirect" title="Tellurium-104">tellurium-104</a>, not counting beta-delayed alpha emission of some lighter elements. The alpha decay sometimes leaves the parent nucleus in an excited state; the emission of a <a href="/wiki/Gamma_ray" title="Gamma ray">gamma ray</a> then removes the excess <a href="/wiki/Energy" title="Energy">energy</a>. </p> <div class="mw-heading mw-heading4"><h4 id="Mechanism_of_production_in_alpha_decay">Mechanism of production in alpha decay</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=4" title="Edit section: Mechanism of production in alpha decay"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In contrast to <a href="/wiki/Beta_decay" title="Beta decay">beta decay</a>, the <a href="/wiki/Fundamental_interaction" title="Fundamental interaction">fundamental interactions</a> responsible for alpha decay are a balance between the <a href="/wiki/Electromagnetic_force" class="mw-redirect" title="Electromagnetic force">electromagnetic force</a> and <a href="/wiki/Nuclear_force" title="Nuclear force">nuclear force</a>. Alpha decay results from the <a href="/wiki/Coulomb%27s_law" title="Coulomb's law">Coulomb repulsion</a><sup id="cite_ref-Krane_4-1" class="reference"><a href="#cite_note-Krane-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> between the alpha particle and the rest of the nucleus, which both have a positive <a href="/wiki/Electric_charge" title="Electric charge">electric charge</a>, but which is kept in check by the <a href="/wiki/Nuclear_force" title="Nuclear force">nuclear force</a>. In <a href="/wiki/Physics_in_the_Classical_Limit" class="mw-redirect" title="Physics in the Classical Limit">classical physics</a>, alpha particles do not have enough energy to escape the <a href="/wiki/Potential_well" title="Potential well">potential well</a> from the strong force inside the nucleus (this well involves escaping the strong force to go up one side of the well, which is followed by the electromagnetic force causing a repulsive push-off down the other side). </p><p>However, the <a href="/wiki/Quantum_tunneling" class="mw-redirect" title="Quantum tunneling">quantum tunnelling</a> effect allows alphas to escape even though they do not have enough energy to overcome the <a href="/wiki/Nuclear_force" title="Nuclear force">nuclear force</a>. This is allowed by the wave nature of matter, which allows the alpha particle to spend some of its time in a region so far from the nucleus that the potential from the repulsive electromagnetic force has fully compensated for the attraction of the nuclear force. From this point, alpha particles can escape. </p> <div class="mw-heading mw-heading3"><h3 id="Ternary_fission">Ternary fission</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=5" title="Edit section: Ternary fission"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Especially energetic alpha particles deriving from a nuclear process are produced in the relatively rare (one in a few hundred) <a href="/wiki/Nuclear_fission" title="Nuclear fission">nuclear fission</a> process of <a href="/wiki/Ternary_fission" title="Ternary fission">ternary fission</a>. In this process, three charged particles are produced from the event instead of the normal two, with the smallest of the charged particles most probably (90% probability) being an alpha particle. Such alpha particles are termed "long range alphas" since at their typical energy of 16 MeV, they are at far higher energy than is ever produced by alpha decay. Ternary fission happens in both neutron-induced fission (the <a href="/wiki/Nuclear_reaction" title="Nuclear reaction">nuclear reaction</a> that happens in a nuclear reactor), and also when <a href="/wiki/Fissionable" class="mw-redirect" title="Fissionable">fissionable</a> and <a href="/wiki/Fissile" class="mw-redirect" title="Fissile">fissile</a> <a href="/wiki/Actinide" title="Actinide">actinides</a> nuclides (i.e., heavy atoms capable of fission) undergo <a href="/wiki/Spontaneous_fission" title="Spontaneous fission">spontaneous fission</a> as a form of radioactive decay. In both induced and spontaneous fission, the higher energies available in heavy nuclei result in long range alphas of higher energy than those from alpha decay. </p> <div class="mw-heading mw-heading3"><h3 id="Accelerators">Accelerators</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=6" title="Edit section: Accelerators"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Energetic helium nuclei (helium ions) may be produced by <a href="/wiki/Cyclotron" title="Cyclotron">cyclotrons</a>, <a href="/wiki/Synchrotron" title="Synchrotron">synchrotrons</a>, and other <a href="/wiki/Particle_accelerator" title="Particle accelerator">particle accelerators</a>. Convention is that they are not normally referred to as "alpha particles".<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2023)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Solar_core_reactions">Solar core reactions</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=7" title="Edit section: Solar core reactions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Helium nuclei may participate in nuclear reactions in stars, and occasionally and historically these have been referred to as alpha reactions (see <a href="/wiki/Triple-alpha_process" title="Triple-alpha process">triple-alpha process</a> and <a href="/wiki/Alpha_process" title="Alpha process">alpha process</a>). </p> <div class="mw-heading mw-heading3"><h3 id="Cosmic_rays">Cosmic rays</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=8" title="Edit section: Cosmic rays"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In addition, extremely high energy helium nuclei sometimes referred to as alpha particles make up about 10 to 12% of <a href="/wiki/Cosmic_ray" title="Cosmic ray">cosmic rays</a>. The mechanisms of cosmic ray production continue to be debated. </p> <div class="mw-heading mw-heading2"><h2 id="Energy_and_absorption">Energy and absorption</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=9" title="Edit section: Energy and absorption"><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:Alpha_decay_energies_example.svg" class="mw-file-description"><img alt="A scatter chart showing 15 examples of some radioactive nuclides with their main emitted alpha particle energies plotted against their atomic number. The range of energies is from about 2 to 12 MeV. Atomic number range is about 50 to 110." src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Alpha_decay_energies_example.svg/330px-Alpha_decay_energies_example.svg.png" decoding="async" width="330" height="240" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Alpha_decay_energies_example.svg/495px-Alpha_decay_energies_example.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Alpha_decay_energies_example.svg/660px-Alpha_decay_energies_example.svg.png 2x" data-file-width="624" data-file-height="453" /></a><figcaption>Example selection of radioactive nuclides with main emitted alpha particle energies plotted against their atomic number.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Each nuclide has a distinct <a href="/wiki/Alpha-particle_spectroscopy" title="Alpha-particle spectroscopy">alpha spectrum</a>.</figcaption></figure> <p>The energy of the alpha particle emitted in <a href="/wiki/Alpha_decay" title="Alpha decay">alpha decay</a> is mildly dependent on the half-life for the emission process, with many orders of magnitude differences in half-life being associated with energy changes of less than 50%, shown by the <a href="/wiki/Geiger%E2%80%93Nuttall_law" title="Geiger–Nuttall law">Geiger–Nuttall law</a>. </p><p>The energy of alpha particles emitted varies, with higher energy alpha particles being emitted from larger nuclei, but most alpha particles have energies of between 3 and 7 <a href="/wiki/MeV" class="mw-redirect" title="MeV">MeV</a> (mega-electron-volts), corresponding to extremely long and extremely short half-lives of alpha-emitting nuclides, respectively. The energies and ratios are often distinct and can be used to identify specific nuclides as in <a href="/wiki/Alpha-particle_spectroscopy" title="Alpha-particle spectroscopy">alpha spectrometry</a>. </p><p>With a typical kinetic energy of 5 MeV; the speed of emitted alpha particles is 15,000 km/s, which is 5% of the speed of light. This energy is a substantial amount of energy for a single particle, but their high mass means alpha particles have a lower speed than any other common type of radiation, e.g. <a href="/wiki/Beta_particle" title="Beta particle">β particles</a>, <a href="/wiki/Neutron_radiation" title="Neutron radiation">neutrons</a>.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>Because of their charge and large mass, alpha particles are easily absorbed by materials, and they can travel only a few centimetres in air. They can be absorbed by tissue paper or by the outer layers of human skin. They typically penetrate skin about 40 <a href="/wiki/Micrometre" title="Micrometre">micrometres</a>, equivalent to a few <a href="/wiki/Cell_(biology)" title="Cell (biology)">cells</a> deep. </p> <div class="mw-heading mw-heading2"><h2 id="Biological_effects">Biological effects</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=10" title="Edit section: Biological effects"><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/Relative_biological_effectiveness" title="Relative biological effectiveness">Relative biological effectiveness</a></div> <p>Due to the short range of absorption and inability to penetrate the outer layers of skin, alpha particles are not, in general, dangerous to life unless the source is ingested or inhaled.<sup id="cite_ref-Christensen2014_13-0" class="reference"><a href="#cite_note-Christensen2014-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> Because of this high mass and strong absorption, if alpha-emitting radionuclides do enter the body (upon being inhaled, ingested, or injected, as with the use of <a href="/wiki/Thorotrast" title="Thorotrast">Thorotrast</a> for high-quality X-ray images prior to the 1950s), alpha radiation is the most destructive form of <a href="/wiki/Ionizing_radiation" title="Ionizing radiation">ionizing radiation</a>. It is the most strongly ionizing, and with large enough doses can cause any or all of the symptoms of <a href="/wiki/Radiation_poisoning" class="mw-redirect" title="Radiation poisoning">radiation poisoning</a>. It is estimated that <a href="/wiki/Chromosome" title="Chromosome">chromosome</a> damage from alpha particles is anywhere from 10 to 1000<sup id="cite_ref-LittleKennedy1985_14-0" class="reference"><a href="#cite_note-LittleKennedy1985-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> times greater than that caused by an equivalent amount of gamma or beta radiation, with the average being set at 20 times. A study of European nuclear workers exposed internally to alpha radiation from plutonium and uranium found that when relative biological effectiveness is considered to be 20, the carcinogenic potential (in terms of lung cancer) of alpha radiation appears to be consistent with that reported for doses of external gamma radiation i.e. a given dose of alpha-particles inhaled presents the same risk as a 20-times higher dose of gamma radiation.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> The powerful alpha emitter <a href="/wiki/Polonium-210" title="Polonium-210">polonium-210</a> (a milligram of <sup>210</sup>Po emits as many alpha particles per second as 4.215 grams of <a href="/wiki/Radium-226" title="Radium-226"><sup>226</sup>Ra</a>) is suspected of playing a role in <a href="/wiki/Lung_cancer" title="Lung cancer">lung cancer</a> and <a href="/wiki/Bladder_cancer" title="Bladder cancer">bladder cancer</a> related to <a href="/wiki/Tobacco_and_health#Radioactive_components_of_tobacco" class="mw-redirect" title="Tobacco and health">tobacco smoking</a>.<sup id="cite_ref-Science_v143_no3603_16-0" class="reference"><a href="#cite_note-Science_v143_no3603-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> <sup>210</sup>Po was used to kill Russian dissident and ex-<a href="/wiki/Federal_Security_Service_of_the_Russian_Federation" class="mw-redirect" title="Federal Security Service of the Russian Federation">FSB</a> officer <a href="/wiki/Alexander_Litvinenko" title="Alexander Litvinenko">Alexander V. Litvinenko</a> in 2006.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="History_of_discovery_and_use">History of discovery and use</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=11" title="Edit section: History of discovery and use"><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:592px;max-width:592px"><div class="trow"><div class="tsingle" style="width:368px;max-width:368px"><div class="thumbimage" style="height:205px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Rutherford_1899_diagram_1.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/35/Rutherford_1899_diagram_1.jpg/366px-Rutherford_1899_diagram_1.jpg" decoding="async" width="366" height="205" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/3/35/Rutherford_1899_diagram_1.jpg 1.5x" data-file-width="392" data-file-height="220" /></a></span></div><div class="thumbcaption">Figure 1 from Rutherford's 1899 paper on uranium radiation.<sup id="cite_ref-Rutherford1899_18-0" class="reference"><a href="#cite_note-Rutherford1899-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup></div></div><div class="tsingle" style="width:220px;max-width:220px"><div class="thumbimage" style="height:205px;overflow:hidden"><span typeof="mw:File"><a href="/wiki/File:Rutherford_1899_diagram_2.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Rutherford_1899_diagram_2.jpg/218px-Rutherford_1899_diagram_2.jpg" decoding="async" width="218" height="206" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Rutherford_1899_diagram_2.jpg/327px-Rutherford_1899_diagram_2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Rutherford_1899_diagram_2.jpg/436px-Rutherford_1899_diagram_2.jpg 2x" data-file-width="487" data-file-height="460" /></a></span></div><div class="thumbcaption">Figure 2 from Rutherford's 1899 paper, graphing the current in relation to the number of layers of foil covering the uranium.</div></div></div></div></div> <p>In 1896, <a href="/wiki/Henri_Becquerel" title="Henri Becquerel">Henri Becquerel</a> discovered that <a href="/wiki/Uranium" title="Uranium">uranium</a> emits an invisible radiation that can leave marks on photographic plates. <a href="/wiki/Marie_Curie" title="Marie Curie">Marie Curie</a> dubbed this phenomenon "radioactivity". <a href="/wiki/Ernest_Rutherford" title="Ernest Rutherford">Ernest Rutherford</a> and <a href="/wiki/J._J._Thomson" title="J. J. Thomson">J. J. Thomson</a> studied uranium radiation and discovered that it could create electrically charged particles in gas (this is what we now call "ionizing radiation"). In 1898, Rutherford discovered that uranium radiation is a mixture of several types of radiation. He performed an experiment which involved two electrodes separated by a small amount of air. He placed some uranium on the bottom electrode, and the radiation from the uranium ionized the air between the electrodes, creating a current. Rutherford then placed a metal foil over the uranium and noticed that the current dropped a bit, indicating that the aluminium foil was absorbing some of the uranium's radiation. Rutherford placed a few more foils over the uranium and found that, for a few foils, the current steadily decreased at a geometric rate. However, after the fourth layer of foil over the uranium, the current didn't drop much and remained more or less level for up to twelve layers of foil (each foil was about 5 micrometers thick). This result indicated that uranium radiation has two components. Rutherford dubbed one component "alpha radiation" which was fully absorbed by just a few layers of foil, and what was left was a second component that could penetrate the foils more easily, and he dubbed the latter "beta radiation".<sup id="cite_ref-Rutherford1899_18-1" class="reference"><a href="#cite_note-Rutherford1899-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p><p>In 1900, <a href="/wiki/Marie_Curie" title="Marie Curie">Marie Curie</a> noticed that the absorption coefficient of alpha rays seemed to increase the thicker the barrier she placed in their path. This suggested that alpha radiation is not a form of light but made of particles that lose kinetic energy as they pass through barriers. In 1902, Rutherford found that he could deflect alpha rays with a magnetic field and an electric field, showing that alpha radiation is composed of positively charged particles.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p><p>Rutherford's work also included measurements of the ratio of an alpha particle's mass to its charge, which led him to the hypothesis that alpha particles were doubly charged helium ions (later shown to be bare helium nuclei).<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> In 1909, <a href="/wiki/Ernest_Rutherford" title="Ernest Rutherford">Ernest Rutherford</a> and <a href="/wiki/Thomas_Royds" title="Thomas Royds">Thomas Royds</a> finally proved that alpha particles were indeed helium ions.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> To do this they collected and purified the gas emitted by radium, a known alpha particle emitter, in a glass tube. An <a href="/wiki/Electric_spark" title="Electric spark">electric spark</a> discharge inside the tube produced light. Subsequent study of the spectra of this light showed that the gas was helium and thus the alpha particles were indeed the helium ions.<sup id="cite_ref-PaisInward_9-1" class="reference"><a href="#cite_note-PaisInward-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 61">: 61 </span></sup> </p><p>Because alpha particles occur naturally, but can have <a href="/wiki/Energy" title="Energy">energy</a> high enough to participate in a <a href="/wiki/Nuclear_reaction" title="Nuclear reaction">nuclear reaction</a>, study of them led to much early knowledge of <a href="/wiki/Nuclear_physics" title="Nuclear physics">nuclear physics</a>. Rutherford used alpha particles emitted by <a href="/wiki/Radium_bromide" title="Radium bromide">radium bromide</a> to infer that <a href="/wiki/J._J._Thomson" title="J. J. Thomson">J. J. Thomson</a>'s <a href="/wiki/Plum_pudding_model" title="Plum pudding model">Plum pudding model</a> of the atom was fundamentally flawed. In <a href="/wiki/Geiger%E2%80%93Marsden_experiment" class="mw-redirect" title="Geiger–Marsden experiment">Rutherford's gold foil experiment</a> conducted by his students <a href="/wiki/Hans_Geiger" title="Hans Geiger">Hans Geiger</a> and <a href="/wiki/Ernest_Marsden" title="Ernest Marsden">Ernest Marsden</a>, a narrow beam of alpha particles was established, passing through very thin (a few hundred atoms thick) gold foil. The alpha particles were detected by a <a href="/wiki/Zinc_sulfide" title="Zinc sulfide">zinc sulfide</a> screen, which emits a flash of light upon an alpha particle collision. Rutherford hypothesized that, assuming the "<a href="/wiki/Plum_pudding_model" title="Plum pudding model">plum pudding</a>" model of the atom was correct, the positively charged alpha particles would be only slightly deflected, if at all, by the dispersed positive charge predicted. </p><p>It was found that some of the alpha particles were deflected at much larger angles than expected (at a suggestion by Rutherford to check it) and some even bounced almost directly back. Although most of the alpha particles went straight through as expected, Rutherford commented that the few particles that were deflected was akin to shooting a fifteen-inch shell at tissue paper only to have it bounce off, again assuming the "plum pudding" theory was correct. It was determined that the atom's positive charge was concentrated in a small area in its center, making the positive charge dense enough to deflect any positively charged alpha particles that came close to what was later termed the nucleus. </p><p>Prior to this discovery, it was not known that alpha particles were themselves atomic nuclei, nor was the existence of protons or neutrons known. After this discovery, J.J. Thomson's "plum pudding" model was abandoned, and Rutherford's experiment led to the <a href="/wiki/Bohr_model" title="Bohr model">Bohr model</a> and later the modern wave-mechanical model of the atom. </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Bragg_Curve_for_Alphas_in_Air-PT-en.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Bragg_Curve_for_Alphas_in_Air-PT-en.svg/220px-Bragg_Curve_for_Alphas_in_Air-PT-en.svg.png" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Bragg_Curve_for_Alphas_in_Air-PT-en.svg/330px-Bragg_Curve_for_Alphas_in_Air-PT-en.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Bragg_Curve_for_Alphas_in_Air-PT-en.svg/440px-Bragg_Curve_for_Alphas_in_Air-PT-en.svg.png 2x" data-file-width="719" data-file-height="478" /></a><figcaption>Energy-loss (<a href="/wiki/Bragg_curve" class="mw-redirect" title="Bragg curve">Bragg curve</a>) in air for typical alpha particle emitted through radioactive decay.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:WolfhartFig1a.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/2/2d/WolfhartFig1a.JPG" decoding="async" width="218" height="174" class="mw-file-element" data-file-width="218" data-file-height="174" /></a><figcaption>The trace of a single alpha particle obtained by nuclear physicist Wolfhart Willimczik with his spark chamber specially made for alpha particles.</figcaption></figure> <p>In 1917, Rutherford went on to use alpha particles to accidentally produce what he later understood as a directed <a href="/wiki/Nuclear_transmutation" title="Nuclear transmutation">nuclear transmutation</a> of one element to another. Transmutation of elements from one to another had been understood since 1901 as a result of natural <a href="/wiki/Radioactive_decay" title="Radioactive decay">radioactive decay</a>, but when Rutherford projected alpha particles from alpha decay into air, he discovered this produced a new type of radiation which proved to be hydrogen nuclei (Rutherford named these <a href="/wiki/Proton" title="Proton">protons</a>). Further experimentation showed the protons to be coming from the nitrogen component of air, and the reaction was deduced to be a transmutation of nitrogen into oxygen in the reaction </p> <style data-mw-deduplicate="TemplateStyles:r996643573">.mw-parser-output .block-indent{padding-left:3em;padding-right:0;overflow:hidden}</style><div class="block-indent"><sup>14</sup>N + α → <sup>17</sup>O + <a href="/wiki/Proton" title="Proton">p</a></div> <p>This was the first discovered <a href="/wiki/Nuclear_reaction" title="Nuclear reaction">nuclear reaction</a>. </p><p>To the adjacent pictures: According to the energy-loss curve by Bragg, it is recognizable that the alpha particle indeed loses more energy on the end of the trace.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Anti-alpha_particle">Anti-alpha particle</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=12" title="Edit section: Anti-alpha particle"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 2011, members of the international <a href="/wiki/STAR_collaboration" class="mw-redirect" title="STAR collaboration">STAR collaboration</a> using the <a href="/wiki/Relativistic_Heavy_Ion_Collider" title="Relativistic Heavy Ion Collider">Relativistic Heavy Ion Collider</a> at the <a href="/wiki/U.S._Department_of_Energy" class="mw-redirect" title="U.S. Department of Energy">U.S. Department of Energy</a>'s <a href="/wiki/Brookhaven_National_Laboratory" title="Brookhaven National Laboratory">Brookhaven National Laboratory</a> detected the <a href="/wiki/Antimatter" title="Antimatter">antimatter</a> partner of the helium nucleus, also known as the anti-alpha.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> The experiment used gold ions moving at nearly the speed of light and colliding head on to produce the antiparticle.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=13" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Devices">Devices</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=14" title="Edit section: Devices"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Some <a href="/wiki/Smoke_detector" title="Smoke detector">smoke detectors</a> contain a small amount of the alpha emitter <a href="/wiki/Americium-241" title="Americium-241">americium-241</a>.<sup id="cite_ref-EPAAmericium_26-0" class="reference"><a href="#cite_note-EPAAmericium-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> The alpha particles <a href="/wiki/Ionization" title="Ionization">ionize</a> air within a small gap. A small <a href="/wiki/Electric_current" title="Electric current">current</a> is passed through that ionized air. Smoke particles from fire that enter the air gap reduce the current flow, sounding the alarm. The isotope is extremely dangerous if inhaled or ingested, but the danger is minimal if the source is kept sealed. Many municipalities have established programs to collect and dispose of old smoke detectors, to keep them out of the general waste stream. However the US EPA says they "may be thrown away with household garbage".<sup id="cite_ref-EPAAmericium_26-1" class="reference"><a href="#cite_note-EPAAmericium-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup></li> <li>Alpha decay can provide a safe power source for <a href="/wiki/Radioisotope_thermoelectric_generator" title="Radioisotope thermoelectric generator">radioisotope thermoelectric generators</a><sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> used for <a href="/wiki/Space_probe" class="mw-redirect" title="Space probe">space probes</a>. Alpha decay is much more easily shielded against than other forms of radioactive decay. <a href="/wiki/Plutonium-238" title="Plutonium-238">Plutonium-238</a>, a source of alpha particles, requires only 2.5 mm of <a href="/wiki/Lead" title="Lead">lead</a> shielding to protect against unwanted radiation.</li> <li><a href="/wiki/Antistatic_devices" class="mw-redirect" title="Antistatic devices">Static eliminators</a> typically use <a href="/wiki/Polonium-210" title="Polonium-210">polonium-210</a>, an alpha emitter, to ionize air, allowing the "<a href="/wiki/Static_cling" title="Static cling">static cling</a>" to more rapidly dissipate.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="Cancer_treatment">Cancer treatment</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=15" title="Edit section: Cancer treatment"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Alpha-emitting <a href="/wiki/Radionuclides" class="mw-redirect" title="Radionuclides">radionuclides</a> are presently being used in three different ways to eradicate cancerous tumors: as an infusible radioactive treatment targeted to specific tissues (radium-223), as a source of radiation inserted directly into solid tumors (radium-224), and as an attachment to an tumor-targeting molecule, such as an antibody to a tumor-associated antigen. </p><p><a href="/wiki/Radium-223" title="Radium-223">Radium-223</a> is an alpha emitter that is naturally attracted to the bone because it is a <a href="/wiki/Calcium" title="Calcium">calcium</a> mimetic. Radium-223 (as radium-223 dichloride) can be infused into a cancer patient's veins, after which it migrates to parts of the bone where there is rapid turnover of cells due to the presence of metastasized tumors. Once within the bone, Ra-223 emits alpha radiation that can destroy tumor cells within a 100-micron distance. This approach has been in use since 2013 to treat <a href="/wiki/Prostate_cancer" title="Prostate cancer">prostate cancer</a> which has metastasized to the bone.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> Radionuclides infused into the circulation are able to reach sites that are accessible to blood vessels. This means, however, that the interior of a large tumor that is not vascularized (i.e. is not well penetrated by blood vessels) may not be effectively eradicated by the radioactivity. </p><p>Radium-224 is a radioactive atom that is utilized as a source of alpha radiation in a cancer treatment device called DaRT (<a href="/wiki/Diffusing_alpha_emitters_radiation_therapy" title="Diffusing alpha emitters radiation therapy">diffusing alpha emitters radiation therapy</a>). Each radium-224 atom undergoes a decay process producing 6 daughter atoms. During this process, 4 alpha particles are emitted. The range of an alpha particle—up to 100 microns—is insufficient to cover the width of many tumors. However, radium-224's daughter atoms can diffuse up to 2–3 mm in the tissue, thus creating a "kill region" with enough radiation to potentially destroy an entire tumor, if the seeds are placed appropriately.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> Radium-224's half-life is short enough at 3.6 days to produce a rapid clinical effect while avoiding the risk of radiation damage due to overexposure. At the same time, the half-life is long enough to allow for handling and shipping the seeds to a cancer treatment center at any location across the globe. </p><p>Targeted alpha therapy for solid tumors involves attaching an alpha-particle-emitting radionuclide to a tumor-targeting molecule such as an antibody, that can be delivered by intravenous administration to a cancer patient.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Alpha_radiation_and_DRAM_errors">Alpha radiation and DRAM errors</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=16" title="Edit section: Alpha radiation and DRAM errors"><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/Soft_error#Alpha_particles_from_package_decay" title="Soft error">Soft error § Alpha particles from package decay</a></div> <p>In computer technology, <a href="/wiki/Dynamic_random_access_memory" class="mw-redirect" title="Dynamic random access memory">dynamic random access memory</a> (DRAM) "<a href="/wiki/Soft_error" title="Soft error">soft errors</a>" were linked to alpha particles in 1978 in <a href="/wiki/Intel" title="Intel">Intel</a>'s DRAM chips. The discovery led to strict control of radioactive elements in the packaging of semiconductor materials, and the problem is largely considered to be solved.<sup id="cite_ref-may79softerrors_33-0" class="reference"><a href="#cite_note-may79softerrors-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=17" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Alpha_nuclide" title="Alpha nuclide">Alpha nuclide</a></li> <li><a href="/wiki/Alpha_process" title="Alpha process">Alpha process</a> (Also known as alpha-capture, or the alpha-ladder)</li> <li><a href="/wiki/Beta_particle" title="Beta particle">Beta particle</a></li> <li><a href="/wiki/Cosmic_ray" title="Cosmic ray">Cosmic rays</a></li> <li><a href="/wiki/Helion_(chemistry)" title="Helion (chemistry)">Helion</a>, the nucleus of <a href="/wiki/Helium-3" title="Helium-3">helium-3</a> rather than <a href="/wiki/Helium-4" title="Helium-4">helium-4</a></li> <li><a href="/wiki/List_of_alpha_emitting_materials" title="List of alpha emitting materials">List of alpha emitting materials</a></li> <li><a href="/wiki/Nuclear_physics" title="Nuclear physics">Nuclear physics</a></li> <li><a href="/wiki/Particle_physics" title="Particle physics">Particle physics</a></li> <li><a href="/wiki/Radionuclide" title="Radionuclide">Radioactive isotope</a></li> <li>Rays: <ul><li><a href="/wiki/Beta_rays" class="mw-redirect" title="Beta rays">β (beta) rays</a></li> <li>γ <a href="/wiki/Gamma_ray" title="Gamma ray">Gamma ray</a></li> <li>δ <a href="/wiki/Delta_ray" title="Delta ray">Delta ray</a></li> <li>ε <a href="/wiki/Epsilon_radiation" class="mw-redirect" title="Epsilon radiation">Epsilon radiation</a></li></ul></li> <li><a href="/wiki/Rutherford_scattering" class="mw-redirect" title="Rutherford scattering">Rutherford scattering</a></li></ul> <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=Alpha_particle&action=edit&section=18" title="Edit section: References"><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-physconst-malpha-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-physconst-malpha_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://physics.nist.gov/cgi-bin/cuu/Value?mal">"2022 CODATA Value: alpha particle mass"</a>. <i>The NIST Reference on Constants, Units, and Uncertainty</i>. <a href="/wiki/National_Institute_of_Standards_and_Technology" title="National Institute of Standards and Technology">NIST</a>. May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">18 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=The+NIST+Reference+on+Constants%2C+Units%2C+and+Uncertainty&rft.atitle=2022+CODATA+Value%3A+alpha+particle+mass&rft.date=2024-05&rft_id=https%3A%2F%2Fphysics.nist.gov%2Fcgi-bin%2Fcuu%2FValue%3Fmal&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-physconst-malphaDa-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-physconst-malphaDa_2-0">^</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="https://physics.nist.gov/cgi-bin/cuu/Value?malu">"2022 CODATA Value: alpha particle mass in u"</a>. <i>The NIST Reference on Constants, Units, and Uncertainty</i>. <a href="/wiki/National_Institute_of_Standards_and_Technology" title="National Institute of Standards and Technology">NIST</a>. May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">18 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=The+NIST+Reference+on+Constants%2C+Units%2C+and+Uncertainty&rft.atitle=2022+CODATA+Value%3A+alpha+particle+mass+in+u&rft.date=2024-05&rft_id=https%3A%2F%2Fphysics.nist.gov%2Fcgi-bin%2Fcuu%2FValue%3Fmalu&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-physconst-malphac2GeV-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-physconst-malphac2GeV_3-0">^</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="https://physics.nist.gov/cgi-bin/cuu/Value?malc2mev">"2022 CODATA Value: alpha particle mass energy equivalent in MeV"</a>. <i>The NIST Reference on Constants, Units, and Uncertainty</i>. <a href="/wiki/National_Institute_of_Standards_and_Technology" title="National Institute of Standards and Technology">NIST</a>. May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">18 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=The+NIST+Reference+on+Constants%2C+Units%2C+and+Uncertainty&rft.atitle=2022+CODATA+Value%3A+alpha+particle+mass+energy+equivalent+in+MeV&rft.date=2024-05&rft_id=https%3A%2F%2Fphysics.nist.gov%2Fcgi-bin%2Fcuu%2FValue%3Fmalc2mev&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-Krane-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-Krane_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Krane_4-1"><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 id="CITEREFKrane1988" class="citation book cs1">Krane, Kenneth S. (1988). <i>Introductory Nuclear Physics</i>. <a href="/wiki/John_Wiley_%26_Sons" class="mw-redirect" title="John Wiley & Sons">John Wiley & Sons</a>. pp. 246–269. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-471-80553-3" title="Special:BookSources/978-0-471-80553-3"><bdi>978-0-471-80553-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Introductory+Nuclear+Physics&rft.pages=246-269&rft.pub=John+Wiley+%26+Sons&rft.date=1988&rft.isbn=978-0-471-80553-3&rft.aulast=Krane&rft.aufirst=Kenneth+S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-:02-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-:02_5-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBohanDinwiddieChallonerStuart2016" class="citation book cs1">Bohan, Elise; Dinwiddie, Robert; Challoner, Jack; Stuart, Colin; Harvey, Derek; <a href="/wiki/Rebecca_Wragg_Sykes" title="Rebecca Wragg Sykes">Wragg-Sykes, Rebecca</a>; <a href="/wiki/Peter_Chrisp" title="Peter Chrisp">Chrisp, Peter</a>; Hubbard, Ben; Parker, Phillip; et al. (Writers) (February 2016). <a rel="nofollow" class="external text" href="https://www.worldcat.org/oclc/940282526"><i>Big History</i></a>. Foreword by <a href="/wiki/David_Christian_(historian)" title="David Christian (historian)">David Christian</a> (1st American ed.). <a href="/wiki/New_York_City" title="New York City">New York</a>: <a href="/wiki/DK_(publisher)" title="DK (publisher)">DK</a>. p. 58. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-4654-5443-0" title="Special:BookSources/978-1-4654-5443-0"><bdi>978-1-4654-5443-0</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/940282526">940282526</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Big+History&rft.place=New+York&rft.pages=58&rft.edition=1st+American&rft.pub=DK&rft.date=2016-02&rft_id=info%3Aoclcnum%2F940282526&rft.isbn=978-1-4654-5443-0&rft.aulast=Bohan&rft.aufirst=Elise&rft.au=Dinwiddie%2C+Robert&rft.au=Challoner%2C+Jack&rft.au=Stuart%2C+Colin&rft.au=Harvey%2C+Derek&rft.au=Wragg-Sykes%2C+Rebecca&rft.au=Chrisp%2C+Peter&rft.au=Hubbard%2C+Ben&rft.au=Parker%2C+Phillip&rft_id=https%3A%2F%2Fwww.worldcat.org%2Foclc%2F940282526&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-RutherfordAlpha-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-RutherfordAlpha_6-0">^</a></b></span> <span class="reference-text">Rutherford distinguished and named α and β rays on page 116 of: E. Rutherford (1899) <a rel="nofollow" class="external text" href="https://books.google.com/books?id=ipMOAAAAIAAJ&pg=PA109">"Uranium radiation and the electrical conduction produced by it,"</a> <i>Philosophical Magazine</i>, Series 5, vol. 47, no. 284, pages 109–163. Rutherford named γ rays on page 177 of: E. Rutherford (1903) <a rel="nofollow" class="external text" href="https://books.google.com/books?id=otXPAAAAMAAJ&pg=PA177">"The magnetic and electric deviation of the easily absorbed rays from radium,"</a> <i>Philosophical Magazine</i>, Series 6, vol. 5, no. 26, pages 177–187.</span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRutherfordGeiger2014" class="citation book cs1">Rutherford, Ernest; Geiger, Hans (2014). "The Charge and Nature of the α-Particle". <i>The Collected Papers of Lord Rutherford of Nelson</i>. Routledge. pp. 109–120.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=The+Charge+and+Nature+of+the+%CE%B1-Particle&rft.btitle=The+Collected+Papers+of+Lord+Rutherford+of+Nelson&rft.pages=109-120&rft.pub=Routledge&rft.date=2014&rft.aulast=Rutherford&rft.aufirst=Ernest&rft.au=Geiger%2C+Hans&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRutherfordGeiger1908" class="citation journal cs1">Rutherford, E.; Geiger, Hans (1908). <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/92981">"The Charge and Nature of the α-Particle"</a>. <i>Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character</i>. <b>81</b> (546): 162–173. <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/1908RSPSA..81..162R">1908RSPSA..81..162R</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.1908.0066">10.1098/rspa.1908.0066</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0950-1207">0950-1207</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/92981">92981</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Proceedings+of+the+Royal+Society+of+London.+Series+A%2C+Containing+Papers+of+a+Mathematical+and+Physical+Character&rft.atitle=The+Charge+and+Nature+of+the+%CE%B1-Particle&rft.volume=81&rft.issue=546&rft.pages=162-173&rft.date=1908&rft_id=info%3Adoi%2F10.1098%2Frspa.1908.0066&rft.issn=0950-1207&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F92981%23id-name%3DJSTOR&rft_id=info%3Abibcode%2F1908RSPSA..81..162R&rft.aulast=Rutherford&rft.aufirst=E.&rft.au=Geiger%2C+Hans&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F92981&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-PaisInward-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-PaisInward_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-PaisInward_9-1"><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 id="CITEREFPais2002" class="citation book cs1">Pais, Abraham (2002). <i>Inward bound: of matter and forces in the physical world</i> (Reprint ed.). Oxford: Clarendon Press [u.a.] <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-19-851997-3" title="Special:BookSources/978-0-19-851997-3"><bdi>978-0-19-851997-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Inward+bound%3A+of+matter+and+forces+in+the+physical+world&rft.place=Oxford&rft.edition=Reprint&rft.pub=Clarendon+Press+%5Bu.a.%5D&rft.date=2002&rft.isbn=978-0-19-851997-3&rft.aulast=Pais&rft.aufirst=Abraham&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMorrisonPine1955" class="citation journal cs1">Morrison, P.; Pine, J. (1955). <a rel="nofollow" class="external text" href="https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.1955.tb35366.x">"Radiogenic Origin of the Helium Isotopes in Rock"</a>. <i>Annals of the New York Academy of Sciences</i>. <b>62</b> (3): 71–92. <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/1955NYASA..62...71M">1955NYASA..62...71M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1111%2Fj.1749-6632.1955.tb35366.x">10.1111/j.1749-6632.1955.tb35366.x</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0077-8923">0077-8923</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Annals+of+the+New+York+Academy+of+Sciences&rft.atitle=Radiogenic+Origin+of+the+Helium+Isotopes+in+Rock&rft.volume=62&rft.issue=3&rft.pages=71-92&rft.date=1955&rft.issn=0077-8923&rft_id=info%3Adoi%2F10.1111%2Fj.1749-6632.1955.tb35366.x&rft_id=info%3Abibcode%2F1955NYASA..62...71M&rft.aulast=Morrison&rft.aufirst=P.&rft.au=Pine%2C+J.&rft_id=https%3A%2F%2Fnyaspubs.onlinelibrary.wiley.com%2Fdoi%2F10.1111%2Fj.1749-6632.1955.tb35366.x&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFirestoneBaglin1999" class="citation book cs1">Firestone, Richard B.; Baglin, Coral M. (1999). <a rel="nofollow" class="external text" href="https://www.worldcat.org/oclc/43118182"><i>Table of isotopes</i></a> (8th ed.). New York: Wiley. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-471-35633-6" title="Special:BookSources/0-471-35633-6"><bdi>0-471-35633-6</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/43118182">43118182</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Table+of+isotopes&rft.place=New+York&rft.edition=8th&rft.pub=Wiley&rft.date=1999&rft_id=info%3Aoclcnum%2F43118182&rft.isbn=0-471-35633-6&rft.aulast=Firestone&rft.aufirst=Richard+B.&rft.au=Baglin%2C+Coral+M.&rft_id=https%3A%2F%2Fwww.worldcat.org%2Foclc%2F43118182&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text">N.B. Since gamma rays are <a href="/wiki/Electromagnetic" class="mw-redirect" title="Electromagnetic">electromagnetic</a> (<a href="/wiki/Light" title="Light">light</a>) they move at the speed of light (<i>c</i>). Beta particles often move at a large fraction of <i>c</i>, and exceed 60% <i>c</i> whenever their energy is > 64 keV, which it commonly is. Neutron velocity from nuclear reactions ranges from about 6% <i>c</i> for fission to as much as 17% <i>c</i> for fusion.</span> </li> <li id="cite_note-Christensen2014-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-Christensen2014_13-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChristensenIddinsSugarman2014" class="citation journal cs1">Christensen, D. M.; Iddins, C. J.; Sugarman, S. L. (2014). "Ionizing radiation injuries and illnesses". <i>Emergency Medicine Clinics of North America</i>. <b>32</b> (1): 245–65. <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%2Fj.emc.2013.10.002">10.1016/j.emc.2013.10.002</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/24275177">24275177</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Emergency+Medicine+Clinics+of+North+America&rft.atitle=Ionizing+radiation+injuries+and+illnesses&rft.volume=32&rft.issue=1&rft.pages=245-65&rft.date=2014&rft_id=info%3Adoi%2F10.1016%2Fj.emc.2013.10.002&rft_id=info%3Apmid%2F24275177&rft.aulast=Christensen&rft.aufirst=D.+M.&rft.au=Iddins%2C+C.+J.&rft.au=Sugarman%2C+S.+L.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-LittleKennedy1985-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-LittleKennedy1985_14-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLittleKennedyMcGandy1985" class="citation journal cs1">Little, John B.; Kennedy, Ann R.; McGandy, Robert B. (1985). "Effect of Dose Rate on the Induction of Experimental Lung Cancer in Hamsters by α Radiation". <i>Radiation Research</i>. <b>103</b> (2): 293–9. <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/1985RadR..103..293L">1985RadR..103..293L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.2307%2F3576584">10.2307/3576584</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a> <a rel="nofollow" class="external text" href="https://www.jstor.org/stable/3576584">3576584</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/4023181">4023181</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Radiation+Research&rft.atitle=Effect+of+Dose+Rate+on+the+Induction+of+Experimental+Lung+Cancer+in+Hamsters+by+%CE%B1+Radiation&rft.volume=103&rft.issue=2&rft.pages=293-9&rft.date=1985&rft_id=info%3Adoi%2F10.2307%2F3576584&rft_id=info%3Apmid%2F4023181&rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F3576584%23id-name%3DJSTOR&rft_id=info%3Abibcode%2F1985RadR..103..293L&rft.aulast=Little&rft.aufirst=John+B.&rft.au=Kennedy%2C+Ann+R.&rft.au=McGandy%2C+Robert+B.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGrellier2017" class="citation journal cs1">Grellier, James; et al. (2017). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5540354">"Risk of lung cancer mortality in nuclear workers from internal exposure to alpha particle-emitting radionuclides"</a>. <i>Epidemiology</i>. <b>28</b> (5): 675–684. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1097%2FEDE.0000000000000684">10.1097/EDE.0000000000000684</a>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5540354">5540354</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/28520643">28520643</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Epidemiology&rft.atitle=Risk+of+lung+cancer+mortality+in+nuclear+workers+from+internal+exposure+to+alpha+particle-emitting+radionuclides&rft.volume=28&rft.issue=5&rft.pages=675-684&rft.date=2017&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC5540354%23id-name%3DPMC&rft_id=info%3Apmid%2F28520643&rft_id=info%3Adoi%2F10.1097%2FEDE.0000000000000684&rft.aulast=Grellier&rft.aufirst=James&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC5540354&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-Science_v143_no3603-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-Science_v143_no3603_16-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRadfordHunt1964" class="citation journal cs1">Radford, Edward P.; Hunt, Vilma R. (1964). "Polonium-210: A Volatile Radioelement in Cigarettes". <i><a href="/wiki/Science_(journal)" title="Science (journal)">Science</a></i>. <b>143</b> (3603): 247–249. <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/1964Sci...143..247R">1964Sci...143..247R</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1126%2Fscience.143.3603.247">10.1126/science.143.3603.247</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/14078362">14078362</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:23455633">23455633</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Science&rft.atitle=Polonium-210%3A+A+Volatile+Radioelement+in+Cigarettes&rft.volume=143&rft.issue=3603&rft.pages=247-249&rft.date=1964&rft_id=info%3Adoi%2F10.1126%2Fscience.143.3603.247&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A23455633%23id-name%3DS2CID&rft_id=info%3Apmid%2F14078362&rft_id=info%3Abibcode%2F1964Sci...143..247R&rft.aulast=Radford&rft.aufirst=Edward+P.&rft.au=Hunt%2C+Vilma+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCowell2006" class="citation news cs1">Cowell, Alan (24 November 2006). <a rel="nofollow" class="external text" href="https://www.nytimes.com/2006/11/24/world/europe/25spycnd.html">"Radiation Poisoning Killed Ex-Russian Spy"</a>. <i>The New York Times</i><span class="reference-accessdate">. Retrieved <span class="nowrap">15 September</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=Radiation+Poisoning+Killed+Ex-Russian+Spy&rft.date=2006-11-24&rft.aulast=Cowell&rft.aufirst=Alan&rft_id=https%3A%2F%2Fwww.nytimes.com%2F2006%2F11%2F24%2Fworld%2Feurope%2F25spycnd.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-Rutherford1899-18"><span class="mw-cite-backlink">^ <a href="#cite_ref-Rutherford1899_18-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Rutherford1899_18-1"><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 id="CITEREFErnest_Rutherford1899" class="citation journal cs1">Ernest Rutherford (1899). <a rel="nofollow" class="external text" href="https://archive.org/details/londonedinburgh5471899lon/page/108/mode/2up">"Uranium Radiation and the Electrical conduction Produced by it"</a>. <i>Philosophical Magazine</i>. <b>47</b> (284): 109–163.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Philosophical+Magazine&rft.atitle=Uranium+Radiation+and+the+Electrical+conduction+Produced+by+it&rft.volume=47&rft.issue=284&rft.pages=109-163&rft.date=1899&rft.au=Ernest+Rutherford&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Flondonedinburgh5471899lon%2Fpage%2F108%2Fmode%2F2up&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFErnest_Rutherford1903" class="citation journal cs1">Ernest Rutherford (1903). <a rel="nofollow" class="external text" href="https://archive.org/details/londonedinburgh651903lond/page/176/mode/2up">"XV. The Magnetic and Electric Deviation of the easily absorbed Rays from Radium"</a>. <i>Philosophical Magazine</i>. 6. <b>5</b>: 177-187.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Philosophical+Magazine&rft.atitle=XV.+The+Magnetic+and+Electric+Deviation+of+the+easily+absorbed+Rays+from+Radium&rft.volume=5&rft.pages=177-187&rft.date=1903&rft.au=Ernest+Rutherford&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Flondonedinburgh651903lond%2Fpage%2F176%2Fmode%2F2up&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text">Heilbron (1968), pp. 252-254</span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHellemansBunch1988" class="citation book cs1">Hellemans, Alexander; Bunch, Bryan (1988). <i>The Timetables of Science</i>. <a href="/wiki/Simon_%26_Schuster" title="Simon & Schuster">Simon & Schuster</a>. p. 411. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0671621300" title="Special:BookSources/0671621300"><bdi>0671621300</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Timetables+of+Science&rft.pages=411&rft.pub=Simon+%26+Schuster&rft.date=1988&rft.isbn=0671621300&rft.aulast=Hellemans&rft.aufirst=Alexander&rft.au=Bunch%2C+Bryan&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRutherfordRoyds1909" class="citation journal cs1">Rutherford, E.; Royds, T. (February 1909). <a rel="nofollow" class="external text" href="https://www.tandfonline.com/doi/full/10.1080/14786440208636599">"XXI. The nature of the α particle from radioactive substances"</a>. <i>The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science</i>. <b>17</b> (98): 281–286. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1080%2F14786440208636599">10.1080/14786440208636599</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1941-5982">1941-5982</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+London%2C+Edinburgh%2C+and+Dublin+Philosophical+Magazine+and+Journal+of+Science&rft.atitle=XXI.+The+nature+of+the+%CE%B1+particle+from+radioactive+substances&rft.volume=17&rft.issue=98&rft.pages=281-286&rft.date=1909-02&rft_id=info%3Adoi%2F10.1080%2F14786440208636599&rft.issn=1941-5982&rft.aulast=Rutherford&rft.aufirst=E.&rft.au=Royds%2C+T.&rft_id=https%3A%2F%2Fwww.tandfonline.com%2Fdoi%2Ffull%2F10.1080%2F14786440208636599&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text">Magazine "nuclear energy" (III/18 (203) special edition, Volume 10, Issue 2 /1967.</span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAgakishievet_al._(STAR_collaboration)2011" class="citation journal cs1">Agakishiev, H.; <i>et al.</i> (<a href="/wiki/STAR_collaboration" class="mw-redirect" title="STAR collaboration">STAR collaboration</a>) (2011). "Observation of the antimatter helium-4 nucleus". <i><a href="/wiki/Nature_(journal)" title="Nature (journal)">Nature</a></i>. <b>473</b> (7347): 353–6. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1103.3312">1103.3312</a></span>. <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/2011Natur.473..353S">2011Natur.473..353S</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%2Fnature10079">10.1038/nature10079</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/21516103">21516103</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:118484566">118484566</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature&rft.atitle=Observation+of+the+antimatter+helium-4+nucleus&rft.volume=473&rft.issue=7347&rft.pages=353-6&rft.date=2011&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A118484566%23id-name%3DS2CID&rft_id=info%3Abibcode%2F2011Natur.473..353S&rft_id=info%3Aarxiv%2F1103.3312&rft_id=info%3Apmid%2F21516103&rft_id=info%3Adoi%2F10.1038%2Fnature10079&rft.aulast=Agakishiev&rft.aufirst=H.&rft.au=%27%27et+al.%27%27+%28STAR+collaboration%29&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span>. See also <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation journal cs1">"Erratum". <i><a href="/wiki/Nature_(journal)" title="Nature (journal)">Nature</a></i>. <b>475</b> (7356): 412. 2011. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1103.3312">1103.3312</a></span>. <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%2Fnature10264">10.1038/nature10264</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:4359058">4359058</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature&rft.atitle=Erratum&rft.volume=475&rft.issue=7356&rft.pages=412&rft.date=2011&rft_id=info%3Aarxiv%2F1103.3312&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A4359058%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1038%2Fnature10264&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</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.physorg.com/news/2011-04-antihelium-physicists-nab-heaviest-antimatter.html">"Antihelium-4: Physicists nab new record for heaviest antimatter"</a>. <a href="/wiki/PhysOrg" class="mw-redirect" title="PhysOrg">PhysOrg</a>. 24 April 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">15 November</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Antihelium-4%3A+Physicists+nab+new+record+for+heaviest+antimatter&rft.pub=PhysOrg&rft.date=2011-04-24&rft_id=http%3A%2F%2Fwww.physorg.com%2Fnews%2F2011-04-antihelium-physicists-nab-heaviest-antimatter.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-EPAAmericium-26"><span class="mw-cite-backlink">^ <a href="#cite_ref-EPAAmericium_26-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-EPAAmericium_26-1"><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.epa.gov/radtown/americium-ionization-smoke-detectors">"Americium in Ionization Smoke Detectors"</a>. <i>U.S. Environmental Protection Agency</i>. 27 November 2018. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230927112506/https://www.epa.gov/radtown/americium-ionization-smoke-detectors">Archived</a> from the original on 27 September 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">30 December</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=U.S.+Environmental+Protection+Agency&rft.atitle=Americium+in+Ionization+Smoke+Detectors&rft.date=2018-11-27&rft_id=https%3A%2F%2Fwww.epa.gov%2Fradtown%2Famericium-ionization-smoke-detectors&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text">Schulman, Fred. "Isotopes and Isotope Thermoelectric Generators." Space Power Systems Advanced Technology Conference. No. N67-10265. 1966.</span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</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://orau.org/health-physics-museum/collection/consumer/miscellaneous/static-eliminators.html">"Static Eliminators (1960s and 1980s)"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">30 December</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Static+Eliminators+%281960s+and+1980s%29&rft_id=https%3A%2F%2Forau.org%2Fhealth-physics-museum%2Fcollection%2Fconsumer%2Fmiscellaneous%2Fstatic-eliminators.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text">Silson, John E. "Hazards in the use of radioactive static eliminators and their control." American Journal of Public Health and the Nation's Health 40.8 (1950): 943-952.</span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFParkerNilssonHeinrich2013" class="citation journal cs1">Parker, C.; Nilsson, S.; Heinrich, D. (18 July 2013). <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/?term=Parker+C&cauthor_id=23863050">"Alpha emitter radium-223 and survival in metastatic prostate cancer"</a>. <i>New England Journal of Medicine</i>. <b>369</b> (3): 213–223. <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/10.1056%2FNEJMoa1213755">10.1056/NEJMoa1213755</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/23863050">23863050</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=New+England+Journal+of+Medicine&rft.atitle=Alpha+emitter+radium-223+and+survival+in+metastatic+prostate+cancer&rft.volume=369&rft.issue=3&rft.pages=213-223&rft.date=2013-07-18&rft_id=info%3Adoi%2F10.1056%2FNEJMoa1213755&rft_id=info%3Apmid%2F23863050&rft.aulast=Parker&rft.aufirst=C.&rft.au=Nilsson%2C+S.&rft.au=Heinrich%2C+D.&rft_id=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F%3Fterm%3DParker%2BC%26cauthor_id%3D23863050&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></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="CITEREFAraziCooksSchmidtKeisari2007" class="citation journal cs1">Arazi, L.; Cooks, T.; Schmidt, M.; Keisari, Y.; Kelson, I. (21 August 2007). <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/17671351/">"Treatment of solid tumors by interstitial release of recoiling short-lived alpha emitters"</a>. <i>Physics in Medicine and Biology</i>. <b>52</b> (16): 5025–42. <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/2007PMB....52.5025A">2007PMB....52.5025A</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F0031-9155%2F52%2F16%2F021">10.1088/0031-9155/52/16/021</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/17671351">17671351</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:1585204">1585204</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Physics+in+Medicine+and+Biology&rft.atitle=Treatment+of+solid+tumors+by+interstitial+release+of+recoiling+short-lived+alpha+emitters&rft.volume=52&rft.issue=16&rft.pages=5025-42&rft.date=2007-08-21&rft_id=info%3Adoi%2F10.1088%2F0031-9155%2F52%2F16%2F021&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A1585204%23id-name%3DS2CID&rft_id=info%3Apmid%2F17671351&rft_id=info%3Abibcode%2F2007PMB....52.5025A&rft.aulast=Arazi&rft.aufirst=L.&rft.au=Cooks%2C+T.&rft.au=Schmidt%2C+M.&rft.au=Keisari%2C+Y.&rft.au=Kelson%2C+I.&rft_id=https%3A%2F%2Fpubmed.ncbi.nlm.nih.gov%2F17671351%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTafreshiDoligalskiTichacekPandya2019" class="citation journal cs1">Tafreshi, Narges K.; Doligalski, Michael L.; Tichacek, Christopher J.; Pandya, Darpan N.; Budzevich, Mikalai M.; El-Haddad, Ghassan; Khushalani, Nikhil I.; Moros, Eduardo G.; McLaughlin, Mark L.; Wadas, Thaddeus J.; Morse, David L. (26 November 2019). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6930656">"Development of Targeted Alpha Particle Therapy for Solid Tumors"</a>. <i>Molecules</i>. <b>24</b> (23): 4314. <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/10.3390%2Fmolecules24234314">10.3390/molecules24234314</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1420-3049">1420-3049</a>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6930656">6930656</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/31779154">31779154</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Molecules&rft.atitle=Development+of+Targeted+Alpha+Particle+Therapy+for+Solid+Tumors&rft.volume=24&rft.issue=23&rft.pages=4314&rft.date=2019-11-26&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC6930656%23id-name%3DPMC&rft.issn=1420-3049&rft_id=info%3Apmid%2F31779154&rft_id=info%3Adoi%2F10.3390%2Fmolecules24234314&rft.aulast=Tafreshi&rft.aufirst=Narges+K.&rft.au=Doligalski%2C+Michael+L.&rft.au=Tichacek%2C+Christopher+J.&rft.au=Pandya%2C+Darpan+N.&rft.au=Budzevich%2C+Mikalai+M.&rft.au=El-Haddad%2C+Ghassan&rft.au=Khushalani%2C+Nikhil+I.&rft.au=Moros%2C+Eduardo+G.&rft.au=McLaughlin%2C+Mark+L.&rft.au=Wadas%2C+Thaddeus+J.&rft.au=Morse%2C+David+L.&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC6930656&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> <li id="cite_note-may79softerrors-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-may79softerrors_33-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMayWoods1979" class="citation journal cs1">May, T. C.; Woods, M. H. (1979). "Alpha-particle-induced soft errors in dynamic memories". <i><a href="/wiki/IEEE_Transactions_on_Electron_Devices" title="IEEE Transactions on Electron Devices">IEEE Transactions on Electron Devices</a></i>. <b>26</b> (1): 2–9. <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/1979ITED...26....2M">1979ITED...26....2M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FT-ED.1979.19370">10.1109/T-ED.1979.19370</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:43748644">43748644</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Transactions+on+Electron+Devices&rft.atitle=Alpha-particle-induced+soft+errors+in+dynamic+memories&rft.volume=26&rft.issue=1&rft.pages=2-9&rft.date=1979&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A43748644%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1109%2FT-ED.1979.19370&rft_id=info%3Abibcode%2F1979ITED...26....2M&rft.aulast=May&rft.aufirst=T.+C.&rft.au=Woods%2C+M.+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=19" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTiplerLlewellyn2002" class="citation book cs1">Tipler, Paul; Llewellyn, Ralph (2002). <i>Modern Physics</i> (4th ed.). <a href="/wiki/W._H._Freeman" class="mw-redirect" title="W. H. Freeman">W. H. Freeman</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-7167-4345-3" title="Special:BookSources/978-0-7167-4345-3"><bdi>978-0-7167-4345-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Modern+Physics&rft.edition=4th&rft.pub=W.+H.+Freeman&rft.date=2002&rft.isbn=978-0-7167-4345-3&rft.aulast=Tipler&rft.aufirst=Paul&rft.au=Llewellyn%2C+Ralph&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAlpha+particle" class="Z3988"></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Alpha_particle&action=edit&section=20" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Commons-logo.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></a></span> Media related to <a href="https://commons.wikimedia.org/wiki/Category:Alpha_particles" class="extiw" title="commons:Category:Alpha particles">Alpha particles</a> at Wikimedia Commons </p> <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><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"></div><div role="navigation" class="navbox" aria-labelledby="Radiation_(physics_and_health)" style="padding:3px"><table class="nowraplinks mw-collapsible uncollapsed 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:Radiation" title="Template:Radiation"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Radiation" title="Template talk:Radiation"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Radiation" title="Special:EditPage/Template:Radiation"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Radiation_(physics_and_health)" style="font-size:114%;margin:0 4em"><a href="/wiki/Radiation" title="Radiation">Radiation</a> (physics and health)</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Main articles</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Non-ionizing_radiation" title="Non-ionizing radiation">Non-ionizing radiation</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acoustic_radiation_force" title="Acoustic radiation force">Acoustic radiation force</a></li> <li><a href="/wiki/Infrared" title="Infrared">Infrared</a></li> <li><a href="/wiki/Light" title="Light">Light</a></li> <li><a href="/wiki/Starlight" title="Starlight">Starlight</a></li> <li><a href="/wiki/Sunlight" title="Sunlight">Sunlight</a></li> <li><a href="/wiki/Microwave" title="Microwave">Microwave</a></li> <li><a href="/wiki/Radio_wave" title="Radio wave">Radio waves</a></li> <li><a href="/wiki/Ultraviolet" title="Ultraviolet">Ultraviolet</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Ionizing_radiation" title="Ionizing radiation">Ionizing radiation</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Radioactive_decay" title="Radioactive decay">Radioactive decay</a></li> <li><a href="/wiki/Cluster_decay" title="Cluster decay">Cluster decay</a></li> <li><a href="/wiki/Background_radiation" title="Background radiation">Background radiation</a></li> <li><a class="mw-selflink selflink">Alpha particle</a></li> <li><a href="/wiki/Beta_particle" title="Beta particle">Beta particle</a></li> <li><a href="/wiki/Gamma_ray" title="Gamma ray">Gamma ray</a></li> <li><a href="/wiki/Cosmic_ray" title="Cosmic ray">Cosmic ray</a></li> <li><a href="/wiki/Neutron_radiation" title="Neutron radiation">Neutron radiation</a></li> <li><a href="/wiki/Nuclear_fission" title="Nuclear fission">Nuclear fission</a></li> <li><a href="/wiki/Nuclear_fusion" title="Nuclear fusion">Nuclear fusion</a></li> <li><a href="/wiki/Nuclear_reactor" title="Nuclear reactor">Nuclear reactors</a></li> <li><a href="/wiki/Nuclear_weapon" title="Nuclear weapon">Nuclear weapons</a></li> <li><a href="/wiki/Particle_accelerator" title="Particle accelerator">Particle accelerators</a></li> <li><a href="/wiki/Radionuclide" title="Radionuclide">Radioactive materials</a></li> <li><a href="/wiki/X-ray" title="X-ray">X-ray</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Earth%27s_energy_budget" title="Earth's energy budget">Earth's energy budget</a></li> <li><a href="/wiki/Electromagnetic_radiation" title="Electromagnetic radiation">Electromagnetic radiation</a></li> <li><a href="/wiki/Synchrotron_radiation" title="Synchrotron radiation">Synchrotron radiation</a></li> <li><a href="/wiki/Thermal_radiation" title="Thermal radiation">Thermal radiation</a></li> <li><a href="/wiki/Black-body_radiation" title="Black-body radiation">Black-body radiation</a></li> <li><a href="/wiki/Particle_radiation" title="Particle radiation">Particle radiation</a></li> <li><a href="/wiki/Gravitational_radiation" class="mw-redirect" title="Gravitational radiation">Gravitational radiation</a></li> <li><a href="/wiki/Cosmic_background_radiation" title="Cosmic background radiation">Cosmic background radiation</a></li> <li><a href="/wiki/Cherenkov_radiation" title="Cherenkov radiation">Cherenkov radiation</a></li> <li><a href="/wiki/Askaryan_radiation" title="Askaryan radiation">Askaryan radiation</a></li> <li><a href="/wiki/Bremsstrahlung" title="Bremsstrahlung">Bremsstrahlung</a></li> <li><a href="/wiki/Unruh_radiation" class="mw-redirect" title="Unruh radiation">Unruh radiation</a></li> <li><a href="/wiki/Dark_radiation" title="Dark radiation">Dark radiation</a></li> <li><a href="/wiki/Radiation_exposure" title="Radiation exposure">Radiation exposure</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Radiation <br />and health</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>Radiation syndrome <ul><li><a href="/wiki/Acute_radiation_syndrome" title="Acute radiation syndrome">acute</a></li> <li><a href="/wiki/Chronic_radiation_syndrome" title="Chronic radiation syndrome">chronic</a></li></ul></li> <li><a href="/wiki/Health_physics" title="Health physics">Health physics</a></li> <li><a href="/wiki/Dosimetry" title="Dosimetry">Dosimetry</a></li> <li><a href="/wiki/Electromagnetic_radiation_and_health" title="Electromagnetic radiation and health">Electromagnetic radiation and health</a></li> <li><a href="/wiki/Laser_safety" title="Laser safety">Laser safety</a></li> <li><a href="/wiki/Lasers_and_aviation_safety" title="Lasers and aviation safety">Lasers and aviation safety</a></li> <li><a href="/wiki/Medical_radiography" class="mw-redirect" title="Medical radiography">Medical radiography</a></li> <li><a href="/wiki/Radiation_protection" title="Radiation protection">Radiation protection</a></li> <li><a href="/wiki/Radiation_therapy" title="Radiation therapy">Radiation therapy</a></li> <li><a href="/wiki/Radiation_damage" title="Radiation damage">Radiation damage</a></li> <li><a href="/wiki/Radioactivity_in_the_life_sciences" title="Radioactivity in the life sciences">Radioactivity in the life sciences</a></li> <li><a href="/wiki/Radioactive_contamination" title="Radioactive contamination">Radioactive contamination</a></li> <li><a href="/wiki/Radiobiology" title="Radiobiology">Radiobiology</a></li> <li><a href="/wiki/Sievert" title="Sievert">Biological dose units and quantities</a></li> <li><a href="/wiki/Wireless_device_radiation_and_health" title="Wireless device radiation and health">Wireless device radiation and health</a></li> <li><a href="/wiki/Wireless_electronic_devices_and_health" class="mw-redirect" title="Wireless electronic devices and health">Wireless electronic devices and health</a></li> <li><a href="/wiki/Heat_transfer" title="Heat transfer">Radiation heat-transfer</a></li> <li><a href="/wiki/Linear_energy_transfer" title="Linear energy transfer">Linear energy transfer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Radiation incidents</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/List_of_civilian_radiation_accidents" title="List of civilian radiation accidents">List of civilian radiation accidents</a></li> <li><a href="/wiki/1996_San_Juan_de_Dios_radiotherapy_accident" title="1996 San Juan de Dios radiotherapy accident">1996 Costa Rica accident</a></li> <li><a href="/wiki/Goi%C3%A2nia_accident" title="Goiânia accident">1987 Goiânia accident</a></li> <li><a href="/wiki/1984_Moroccan_radiation_accident" title="1984 Moroccan radiation accident">1984 Moroccan accident</a></li> <li><a href="/wiki/1990_Clinic_of_Zaragoza_radiotherapy_accident" class="mw-redirect" title="1990 Clinic of Zaragoza radiotherapy accident">1990 Zaragoza accident</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related articles</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/Half-life" title="Half-life">Half-life</a></li> <li><a href="/wiki/Nuclear_physics" title="Nuclear physics">Nuclear physics</a></li> <li><a href="/wiki/Radioactive_source" title="Radioactive source">Radioactive source</a></li> <li><a href="/wiki/Radiation_hardening" title="Radiation hardening">Radiation hardening</a></li> <li><a href="/wiki/Havana_syndrome" title="Havana syndrome">Havana syndrome</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><div role="note" class="hatnote navigation-not-searchable selfref">See also the categories <a href="/wiki/Category:Radiation_effects" title="Category:Radiation effects">Radiation effects</a>, <a href="/wiki/Category:Radioactivity" title="Category:Radioactivity">Radioactivity</a>, <a href="/wiki/Category:Radiobiology" title="Category:Radiobiology">Radiobiology</a>, and <a href="/wiki/Category:Radiation_protection" title="Category:Radiation protection">Radiation protection</a></div></div></td></tr></tbody></table></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-label="Navbox" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a>: National <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q103517#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></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://d-nb.info/gnd/4142014-7">Germany</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/sh85003816">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&local_base=NLX10&find_code=UID&request=987007294757305171">Israel</a></span></li></ul></div></td></tr></tbody></table></div>    </div><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=Alpha_particle&oldid=1259190901">https://en.wikipedia.org/w/index.php?title=Alpha_particle&oldid=1259190901</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:Helium" title="Category:Helium">Helium</a></li><li><a href="/wiki/Category:Ionizing_radiation" title="Category:Ionizing radiation">Ionizing radiation</a></li><li><a href="/wiki/Category:Radioactivity" title="Category:Radioactivity">Radioactivity</a></li><li><a href="/wiki/Category:Subatomic_particles_with_spin_0" title="Category:Subatomic particles with spin 0">Subatomic particles with spin 0</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:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Use_dmy_dates_from_September_2024" title="Category:Use dmy dates from September 2024">Use dmy dates from September 2024</a></li><li><a href="/wiki/Category:All_articles_with_unsourced_statements" title="Category:All articles with unsourced statements">All articles with unsourced statements</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_February_2023" title="Category:Articles with unsourced statements from February 2023">Articles with unsourced statements from February 2023</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><li><a href="/wiki/Category:Commons_category_link_from_Wikidata" title="Category:Commons category link from Wikidata">Commons category link from Wikidata</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 23 November 2024, at 21:42<span class="anonymous-show"> (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=Alpha_particle&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-ckdzv","wgBackendResponseTime":142,"wgPageParseReport":{"limitreport":{"cputime":"0.792","walltime":"1.032","ppvisitednodes":{"value":5423,"limit":1000000},"postexpandincludesize":{"value":107461,"limit":2097152},"templateargumentsize":{"value":4227,"limit":2097152},"expansiondepth":{"value":16,"limit":100},"expensivefunctioncount":{"value":8,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":129315,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 847.233 1 -total"," 34.50% 292.272 1 Template:Reflist"," 14.81% 125.472 1 Template:Radiation"," 14.52% 122.992 2 Template:Navbox"," 13.88% 117.607 1 Template:Infobox_Particle"," 12.98% 109.968 1 Template:Infobox"," 12.51% 105.981 6 Template:Cite_web"," 12.06% 102.194 15 Template:Cite_journal"," 8.62% 73.042 3 Template:Physconst"," 8.04% 68.133 1 Template:Short_description"]},"scribunto":{"limitreport-timeusage":{"value":"0.468","limit":"10.000"},"limitreport-memusage":{"value":10054565,"limit":52428800}},"cachereport":{"origin":"mw-api-ext.codfw.main-7556f8b5dd-sqd8n","timestamp":"20241123214228","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Alpha particle","url":"https:\/\/en.wikipedia.org\/wiki\/Alpha_particle","sameAs":"http:\/\/www.wikidata.org\/entity\/Q103517","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q103517","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":"2002-02-05T09:01:12Z","dateModified":"2024-11-23T21:42:27Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/7\/79\/Alpha_Decay.svg","headline":"helium-4 nucleus; particle of two protons and two neutrons"}</script> </body> </html>