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class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><i>s</i>-process</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 21 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-21" 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">21 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B9%D9%85%D9%84%D9%8A%D8%A9_%D8%A7%D9%84%D8%AA%D9%82%D8%A7%D8%B7_%D8%A7%D9%84%D9%86%D9%8A%D9%88%D8%AA%D8%B1%D9%88%D9%86_%D8%A7%D9%84%D8%A8%D8%B7%D9%8A%D8%A6%D8%A9" title="عملية التقاط النيوترون البطيئة – Arabic" lang="ar" hreflang="ar" data-title="عملية التقاط النيوترون البطيئة" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/S-%D0%BF%D1%80%D0%BE%D1%86%D0%B5%D1%81" title="S-процес – Bulgarian" lang="bg" hreflang="bg" data-title="S-процес" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Proc%C3%A9s_S" title="Procés S – Catalan" lang="ca" hreflang="ca" data-title="Procés S" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/S-Prozess" title="S-Prozess – German" lang="de" hreflang="de" data-title="S-Prozess" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Processus_s" title="Processus s – French" lang="fr" hreflang="fr" data-title="Processus s" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/S%EA%B3%BC%EC%A0%95" title="S과정 – Korean" lang="ko" hreflang="ko" data-title="S과정" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Proses_s" title="Proses s – Indonesian" lang="id" hreflang="id" data-title="Proses s" 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/Processo_s" title="Processo s – Italian" lang="it" hreflang="it" data-title="Processo s" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/S_procesas" title="S procesas – Lithuanian" lang="lt" hreflang="lt" data-title="S procesas" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Proses-S" title="Proses-S – Malay" lang="ms" hreflang="ms" data-title="Proses-S" 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-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/S%E9%81%8E%E7%A8%8B" title="S過程 – Japanese" lang="ja" hreflang="ja" data-title="S過程" 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-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Proces_s" title="Proces s – Polish" lang="pl" hreflang="pl" data-title="Proces s" 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/Processo_s" title="Processo s – Portuguese" lang="pt" hreflang="pt" data-title="Processo s" 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/Proces_s" title="Proces s – Romanian" lang="ro" hreflang="ro" data-title="Proces s" 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/S-%D0%BF%D1%80%D0%BE%D1%86%D0%B5%D1%81%D1%81" title="S-процесс – Russian" lang="ru" hreflang="ru" data-title="S-процесс" 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/S-process" title="S-process – Sinhala" lang="si" hreflang="si" data-title="S-process" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/S-processen" title="S-processen – Swedish" lang="sv" hreflang="sv" data-title="S-processen" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%81%E0%B8%A3%E0%B8%B0%E0%B8%9A%E0%B8%A7%E0%B8%99%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B9%80%E0%B8%AD%E0%B8%AA" title="กระบวนการเอส – Thai" lang="th" hreflang="th" data-title="กระบวนการเอส" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/S-%D0%BF%D1%80%D0%BE%D1%86%D0%B5%D1%81" title="S-процес – Ukrainian" lang="uk" hreflang="uk" data-title="S-процес" 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/Qu%C3%A1_tr%C3%ACnh_s" title="Quá trình s – Vietnamese" lang="vi" hreflang="vi" data-title="Quá trình s" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/S%E9%81%8E%E7%A8%8B" title="S過程 – Chinese" lang="zh" hreflang="zh" data-title="S過程" 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/Q277209#sitelinks-wikipedia" title="Edit interlanguage links" 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href="https://www.wikidata.org/wiki/Special:EntityPage/Q277209" 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">Nucleosynthesis pathway</div> <p>The <b>slow neutron-capture process</b>, or <b><i>s</i>-process</b>, is a series of <a href="/wiki/Nuclear_reactions" class="mw-redirect" title="Nuclear reactions">reactions</a> in <a href="/wiki/Nuclear_astrophysics" title="Nuclear astrophysics">nuclear astrophysics</a> that occur in stars, particularly <a href="/wiki/Asymptotic_giant_branch_stars" class="mw-redirect" title="Asymptotic giant branch stars">asymptotic giant branch stars</a>. The <i>s</i>-process is responsible for the creation (<a href="/wiki/Nucleosynthesis" title="Nucleosynthesis">nucleosynthesis</a>) of approximately half the <a href="/wiki/Atomic_nucleus" title="Atomic nucleus">atomic nuclei</a> <a href="/wiki/Heavy_metal_(chemical_element)" class="mw-redirect" title="Heavy metal (chemical element)">heavier than iron</a>. </p><p>In the <i>s</i>-process, a <a href="/wiki/Seed_nucleus" title="Seed nucleus">seed nucleus</a> undergoes <a href="/wiki/Neutron_capture" title="Neutron capture">neutron capture</a> to form an <a href="/wiki/Isotope" title="Isotope">isotope</a> with one higher <a href="/wiki/Atomic_mass" title="Atomic mass">atomic mass</a>. If the new isotope is <a href="/wiki/Stable_nuclide" title="Stable nuclide">stable</a>, a series of increases in mass can occur, but if it is <a href="/wiki/Unstable_nucleus" class="mw-redirect" title="Unstable nucleus">unstable</a>, then <a href="/wiki/Beta_decay" title="Beta decay">beta decay</a> will occur, producing an element of the next higher <a href="/wiki/Atomic_number" title="Atomic number">atomic number</a>. The process is <i>slow</i> (hence the name) in the sense that there is sufficient time for this <a href="/wiki/Radioactive_decay" title="Radioactive decay">radioactive decay</a> to occur before another neutron is captured. A series of these reactions produces stable isotopes by moving along the <a href="/wiki/Valley_of_stability" title="Valley of stability">valley</a> of <a href="/wiki/Beta-decay_stable_isobars" title="Beta-decay stable isobars">beta-decay stable isobars</a> in the <a href="/wiki/Table_of_nuclides" title="Table of nuclides">table of nuclides</a>. </p><p>A range of elements and isotopes can be produced by the <i>s</i>-process, because of the intervention of <a href="/wiki/Alpha_decay" title="Alpha decay">alpha decay</a> steps along the reaction chain. The relative abundances of elements and isotopes produced depends on the source of the neutrons and how their flux changes over time. Each branch of the <i>s</i>-process reaction chain eventually terminates at a cycle involving <a href="/wiki/Lead" title="Lead">lead</a>, <a href="/wiki/Bismuth" title="Bismuth">bismuth</a>, and <a href="/wiki/Polonium" title="Polonium">polonium</a>. </p><p>The <i>s</i>-process contrasts with the <a href="/wiki/R-process" title="R-process"><i>r</i>-process</a>, in which successive neutron captures are <i>rapid</i>: they happen more quickly than the beta decay can occur. The <i>r</i>-process dominates in environments with higher fluxes of <a href="/wiki/Free_neutron" class="mw-redirect" title="Free neutron">free neutrons</a>; it produces heavier elements and more neutron-rich isotopes than the <i>s</i>-process. Together the two processes account for most of the relative <a href="/wiki/Abundance_of_chemical_elements" class="mw-redirect" title="Abundance of chemical elements">abundance of chemical elements</a> heavier than iron. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=S-process&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <i>s</i>-process was seen to be needed from the relative abundances of isotopes of heavy elements and from a newly published table of <a href="/wiki/Abundance_of_the_chemical_elements" title="Abundance of the chemical elements">abundances</a> by <a href="/wiki/Hans_Suess" title="Hans Suess">Hans Suess</a> and <a href="/wiki/Harold_Urey" title="Harold Urey">Harold Urey</a> in 1956.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Among other things, these data showed abundance peaks for <a href="/wiki/Strontium" title="Strontium">strontium</a>, <a href="/wiki/Barium" title="Barium">barium</a>, and <a href="/wiki/Lead" title="Lead">lead</a>, which, according to <a href="/wiki/Quantum_mechanics" title="Quantum mechanics">quantum mechanics</a> and the <a href="/wiki/Nuclear_shell_model" title="Nuclear shell model">nuclear shell model</a>, are particularly stable nuclei, much like the <a href="/wiki/Noble_gas" title="Noble gas">noble gases</a> are chemically <a href="/wiki/Inert_gas" title="Inert gas">inert</a>. This implied that some abundant nuclei must be created by slow <a href="/wiki/Neutron_capture" title="Neutron capture">neutron capture</a>, and it was only a matter of determining how other nuclei could be accounted for by such a process. A table apportioning the heavy isotopes between <i>s</i>-process and <a href="/wiki/R-process" title="R-process"><i>r</i>-process</a> was published in the famous <a href="/wiki/B2FH_paper" title="B2FH paper">B<sup>2</sup>FH review paper</a> in 1957.<sup id="cite_ref-Synthesis_of_the_Elements_in_Stars_2-0" class="reference"><a href="#cite_note-Synthesis_of_the_Elements_in_Stars-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> There it was also argued that the <i>s</i>-process occurs in <a href="/wiki/Red_giant" title="Red giant">red giant</a> stars. In a particularly illustrative case, the element <a href="/wiki/Technetium" title="Technetium">technetium</a>, whose longest half-life is 4.2 million years, had been discovered in s-, M-, and N-type stars in 1952<sup id="cite_ref-CRC_3-0" class="reference"><a href="#cite_note-CRC-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> by <a href="/wiki/Paul_W._Merrill" title="Paul W. Merrill">Paul W. Merrill</a>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Since these stars were thought to be billions of years old, the presence of technetium in their outer atmospheres was taken as evidence of its recent creation there, probably unconnected with the nuclear fusion in the deep interior of the star that provides its power. </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Nucleosynthesis_periodic_table.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Nucleosynthesis_periodic_table.svg/500px-Nucleosynthesis_periodic_table.svg.png" decoding="async" width="500" height="250" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Nucleosynthesis_periodic_table.svg/750px-Nucleosynthesis_periodic_table.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/31/Nucleosynthesis_periodic_table.svg/1000px-Nucleosynthesis_periodic_table.svg.png 2x" data-file-width="512" data-file-height="256" /></a><figcaption>Periodic table showing the cosmogenic origin of each element. The elements heavier than iron with origins in <i>dying low-mass stars</i> are typically those produced by the <i>s</i>-process, which is characterized by slow neutron diffusion and capture over long periods in such stars.</figcaption></figure> <p>A calculable model for creating the heavy isotopes from iron seed nuclei in a time-dependent manner was not provided until 1961.<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> That work showed that the large overabundances of barium observed by astronomers in certain red-giant stars could be created from iron seed nuclei if the total neutron flux (number of neutrons per unit area) was appropriate. It also showed that no one single value for neutron flux could account for the observed <i>s</i>-process abundances, but that a wide range is required. The numbers of iron seed nuclei that were exposed to a given flux must decrease as the flux becomes stronger. This work also showed that the curve of the product of neutron-capture cross section times abundance is not a smoothly falling curve, as <a href="/wiki/B2FH" class="mw-redirect" title="B2FH">B<sup>2</sup>FH</a> had sketched, but rather has a <i>ledge-precipice structure</i>. A series of papers<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-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><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><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><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><sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> in the 1970s by <a href="/wiki/Donald_D._Clayton" title="Donald D. Clayton">Donald D. Clayton</a> utilizing an exponentially declining neutron flux as a function of the number of iron seed exposed became the standard model of the <i>s</i>-process and remained so until the details of <a href="/wiki/Asymptotic_Giant_Branch" class="mw-redirect" title="Asymptotic Giant Branch">AGB-star</a> nucleosynthesis became sufficiently advanced that they became a standard model for <i>s</i>-process element formation based on stellar structure models. Important series of measurements of neutron-capture cross sections were reported from Oak Ridge National Lab in 1965<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> and by Karlsruhe Nuclear Physics Center in 1982<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> and subsequently, these placed the <i>s</i>-process on the firm quantitative basis that it enjoys today.<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. (October 2019)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="The_s-process_in_stars">The <i>s</i>-process in stars</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=S-process&action=edit&section=2" title="Edit section: The s-process in stars"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <i>s</i>-process is believed to occur mostly in <a href="/wiki/Asymptotic_giant_branch" title="Asymptotic giant branch">asymptotic giant branch</a> stars, seeded by iron nuclei left by a supernova during a previous generation of stars. In contrast to the <i>r</i>-process which is believed to occur over time scales of seconds in explosive environments, the <i>s</i>-process is believed to occur over time scales of thousands of years, passing decades between neutron captures. The extent to which the <i>s</i>-process moves up the elements in the chart of isotopes to higher <a href="/wiki/Mass_number" title="Mass number">mass numbers</a> is essentially determined by the degree to which the star in question is able to produce <a href="/wiki/Neutron" title="Neutron">neutrons</a>. The quantitative yield is also proportional to the amount of iron in the star's initial abundance distribution. <a href="/wiki/Iron" title="Iron">Iron</a> is the "starting material" (or seed) for this neutron capture-beta minus decay sequence of synthesizing new elements.<sup id="cite_ref-Reifarth2010_16-0" class="reference"><a href="#cite_note-Reifarth2010-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p><p>The main <a href="/wiki/Neutron_source" title="Neutron source">neutron source</a> reactions are: </p> <dl><dd><table border="0"> <tbody><tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Carbon-13" title="Carbon-13"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">13</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">6</sub></span></span>C<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Helium-4" title="Helium-4"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Oxygen-16" title="Oxygen-16"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">16</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">8</sub></span></span>O<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td></tr> <tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Neon-22" class="mw-redirect" title="Neon-22"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">22</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">10</sub></span></span>Ne<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Helium-4" title="Helium-4"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Magnesium-25" class="mw-redirect" title="Magnesium-25"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">25</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">12</sub></span></span>Mg<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td></tr></tbody></table></dd></dl> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:S-process-elem-Ag-to-Sb.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/S-process-elem-Ag-to-Sb.svg/400px-S-process-elem-Ag-to-Sb.svg.png" decoding="async" width="400" height="184" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/S-process-elem-Ag-to-Sb.svg/600px-S-process-elem-Ag-to-Sb.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4e/S-process-elem-Ag-to-Sb.svg/800px-S-process-elem-Ag-to-Sb.svg.png 2x" data-file-width="740" data-file-height="340" /></a><figcaption>The <i>s</i>-process acting in the range from <a href="/wiki/Silver" title="Silver">Ag</a> to <a href="/wiki/Antimony" title="Antimony">Sb</a></figcaption></figure> <p>One distinguishes the main and the weak <i>s</i>-process component. The main component produces heavy elements beyond <a href="/wiki/Strontium" title="Strontium">Sr</a> and <a href="/wiki/Yttrium" title="Yttrium">Y</a>, and up to <a href="/wiki/Lead" title="Lead">Pb</a> in the lowest metallicity stars. The production sites of the main component are low-mass asymptotic giant branch stars.<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> The main component relies on the <sup>13</sup>C neutron source above.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> The weak component of the <i>s</i>-process, on the other hand, synthesizes <i>s</i>-process isotopes of elements from iron group seed nuclei to <sup>58</sup>Fe on up to Sr and Y, and takes place at the end of <a href="/wiki/Helium_fusion" class="mw-redirect" title="Helium fusion">helium</a>- and <a href="/wiki/Carbon-burning_process" title="Carbon-burning process">carbon-burning</a> in massive stars. It employs primarily the <sup>22</sup>Ne neutron source. These stars will become supernovae at their demise and spew those <i>s</i>-process isotopes into interstellar gas. </p><p>The <i>s</i>-process is sometimes approximated over a small mass region using the so-called "local approximation", by which the ratio of abundances is inversely proportional to the ratio of neutron-capture cross-sections for nearby isotopes on the <i>s</i>-process path. This approximation is – as the name indicates – only valid locally, meaning for isotopes of nearby mass numbers, but it is invalid at magic numbers where the ledge-precipice structure dominates. </p> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:S-R-processes-atomic-mass-201-to-210.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/S-R-processes-atomic-mass-201-to-210.svg/250px-S-R-processes-atomic-mass-201-to-210.svg.png" decoding="async" width="250" height="193" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/S-R-processes-atomic-mass-201-to-210.svg/375px-S-R-processes-atomic-mass-201-to-210.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6b/S-R-processes-atomic-mass-201-to-210.svg/500px-S-R-processes-atomic-mass-201-to-210.svg.png 2x" data-file-width="440" data-file-height="340" /></a><figcaption>Chart representing the final part of the <i>s</i>-process. Red horizontal lines with a circle in their right ends represent <a href="/wiki/Neutron_capture" title="Neutron capture">neutron captures</a>; blue arrows pointing up-left represent <a href="/wiki/Beta_decay" title="Beta decay">beta decays</a>; green arrows pointing down-left represent <a href="/wiki/Alpha_decay" title="Alpha decay">alpha decays</a>; cyan/light-green arrows pointing down-right represent <a href="/wiki/Electron_capture" title="Electron capture">electron captures</a>.</figcaption></figure> <p>Because of the relatively low <a href="/wiki/Neutron_flux" title="Neutron flux">neutron fluxes</a> expected to occur during the <i>s</i>-process (on the order of 10<sup>5</sup> to 10<sup>11</sup> neutrons per cm<sup>2</sup> per second), this process does not have the ability to produce any of the heavy radioactive isotopes such as <a href="/wiki/Thorium" title="Thorium">thorium</a> or <a href="/wiki/Uranium" title="Uranium">uranium</a>. The cycle that terminates the <i>s</i>-process is: </p><p><span style="white-space:nowrap;"><a href="/wiki/Bismuth-209" title="Bismuth-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> captures a neutron, producing <span style="white-space:nowrap;"><a href="/wiki/Bismuth-210" class="mw-redirect" title="Bismuth-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span>, which decays to <span style="white-space:nowrap;"><a href="/wiki/Polonium-210" title="Polonium-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Po<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> by <a href="/wiki/Beta_decay" title="Beta decay">β<sup>−</sup> decay</a>. <span style="white-space:nowrap;"><a href="/wiki/Polonium-210" title="Polonium-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Po<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> in turn decays to <span style="white-space:nowrap;"><a href="/wiki/Lead-206" class="mw-redirect" title="Lead-206"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">206</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> by <a href="/wiki/Alpha_decay" title="Alpha decay">α decay</a>: </p> <dl><dd><table border="0"> <tbody><tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Bismuth-209" title="Bismuth-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">83</sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Bismuth-210" class="mw-redirect" title="Bismuth-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">83</sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span class="texhtml"><span style="white-space:nowrap;"><a href="/wiki/Gamma_ray" title="Gamma ray"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>γ<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span></span> </td></tr> <tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Bismuth-210" class="mw-redirect" title="Bismuth-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">83</sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td> </td> <td> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Polonium-210" title="Polonium-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">84</sub></span></span>Po<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Electron" title="Electron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>e<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">−</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span class="texhtml"><span style="white-space:nowrap;"><a href="/wiki/Electron_antineutrino" class="mw-redirect" title="Electron antineutrino"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span><span style="text-decoration:overline;">ν</span><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">e</sub></span></span></a></span></span> </td></tr> <tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Polonium-210" title="Polonium-210"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">210</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">84</sub></span></span>Po<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td> </td> <td> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Lead-206" class="mw-redirect" title="Lead-206"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">206</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">82</sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Helium-4" title="Helium-4"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td></tr></tbody></table></dd></dl> <p><span style="white-space:nowrap;"><a href="/wiki/Lead-206" class="mw-redirect" title="Lead-206"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">206</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> then captures three neutrons, producing <span style="white-space:nowrap;"><a href="/wiki/Lead-209" class="mw-redirect" title="Lead-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span>, which decays to <span style="white-space:nowrap;"><a href="/wiki/Bismuth-209" title="Bismuth-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> by β<sup>−</sup> decay, restarting the cycle: </p> <dl><dd><table border="0"> <tbody><tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Lead-206" class="mw-redirect" title="Lead-206"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">206</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">82</sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td>3 <span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Lead-209" class="mw-redirect" title="Lead-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">82</sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td></tr> <tr style="height:2em;"> <td><span style="white-space:nowrap;"><a href="/wiki/Lead-209" class="mw-redirect" title="Lead-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">82</sub></span></span>Pb<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td> </td> <td> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Bismuth-209" title="Bismuth-209"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">209</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">83</sub></span></span>Bi<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td> <span style="white-space:nowrap;"><a href="/wiki/Electron" title="Electron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>e<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">−</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td> <span class="texhtml"><span style="white-space:nowrap;"><a href="/wiki/Electron_antineutrino" class="mw-redirect" title="Electron antineutrino"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span><span style="text-decoration:overline;">ν</span><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">e</sub></span></span></a></span></span> </td></tr></tbody></table></dd></dl> <p>The net result of this cycle therefore is that 4 <a href="/wiki/Neutron" title="Neutron">neutrons</a> are converted into one <a href="/wiki/Alpha_particle" title="Alpha particle">alpha particle</a>, two <a href="/wiki/Electron" title="Electron">electrons</a>, two anti-electron <a href="/wiki/Neutrino" title="Neutrino">neutrinos</a> and <a href="/wiki/Gamma_ray" title="Gamma ray">gamma radiation</a>: </p> <dl><dd><table border="0"> <tbody><tr style="height:2em;"> <td> </td> <td> </td> <td>4 <span style="white-space:nowrap;"><a href="/wiki/Neutron" title="Neutron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>n<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>→ </td> <td><span style="white-space:nowrap;"><a href="/wiki/Helium-4" title="Helium-4"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">4</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">2</sub></span></span>He<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td>2 <span style="white-space:nowrap;"><a href="/wiki/Electron" title="Electron"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>e<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">−</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span> </td> <td>+ </td> <td>2 <span class="texhtml"><span style="white-space:nowrap;"><a href="/wiki/Electron_antineutrino" class="mw-redirect" title="Electron antineutrino"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span><span style="text-decoration:overline;">ν</span><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">e</sub></span></span></a></span></span> </td> <td>+ </td> <td><span class="texhtml"><span style="white-space:nowrap;"><a href="/wiki/Gamma_ray" title="Gamma ray"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:right"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>γ<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.8em;line-height:1.0em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span></a></span></span> </td></tr></tbody></table></dd></dl> <p>The process thus terminates in bismuth, the heaviest "stable" element, and polonium, the first non-primordial element after bismuth. Bismuth is actually slightly radioactive, but with a half-life so long—a billion times the present age of the universe—that it is effectively stable over the lifetime of any existing star. <a href="/wiki/Polonium-210" title="Polonium-210">Polonium-210</a>, however, decays with a half-life of 138 days to stable <a href="/wiki/Lead-206" class="mw-redirect" title="Lead-206">lead-206</a>. </p> <div class="mw-heading mw-heading2"><h2 id="The_s-process_measured_in_stardust">The <i>s</i>-process measured in stardust</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=S-process&action=edit&section=3" title="Edit section: The s-process measured in stardust"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Stardust is one component of <a href="/wiki/Cosmic_dust" title="Cosmic dust">cosmic dust</a>. Stardust is individual solid grains that condensed during mass loss from various long-dead stars. Stardust existed throughout interstellar gas before the birth of the Solar System and was trapped in meteorites when they assembled from interstellar matter contained in the planetary accretion disk in early Solar System. Today they are found in meteorites, where they have been preserved. Meteoriticists habitually refer to them as <a href="/wiki/Presolar_grains" title="Presolar grains">presolar grains</a>. The <i>s</i>-process enriched grains are mostly <a href="/wiki/Silicon_carbide" title="Silicon carbide">silicon carbide</a> (SiC). The origin of these grains is demonstrated by laboratory measurements of extremely unusual isotopic abundance ratios within the grain. First experimental detection of <i>s</i>-process xenon isotopes was made in 1978,<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> confirming earlier predictions that <i>s</i>-process isotopes would be enriched, nearly pure, in stardust from red giant stars.<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> These discoveries launched new insight into astrophysics and into the origin of meteorites in the Solar System.<sup id="cite_ref-Clayton2004_21-0" class="reference"><a href="#cite_note-Clayton2004-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> Silicon carbide (SiC) grains condense in the atmospheres of <a href="/wiki/Asymptotic_Giant_Branch" class="mw-redirect" title="Asymptotic Giant Branch">AGB stars</a> and thus trap isotopic abundance ratios as they existed in that star. Because the AGB stars are the main site of the <i>s</i>-process in the galaxy, the heavy elements in the SiC grains contain almost pure <i>s</i>-process isotopes in elements heavier than iron. This fact has been demonstrated repeatedly by sputtering-ion mass spectrometer studies of these stardust <a href="/wiki/Presolar_grains" title="Presolar grains">presolar grains</a>.<sup id="cite_ref-Clayton2004_21-1" class="reference"><a href="#cite_note-Clayton2004-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> Several surprising results have shown that within them the ratio of <i>s</i>-process and <i>r</i>-process abundances is somewhat different from that which was previously assumed. It has also been shown with trapped isotopes of <a href="/wiki/Krypton" title="Krypton">krypton</a> and <a href="/wiki/Xenon" title="Xenon">xenon</a> that the <i>s</i>-process abundances in the AGB-star atmospheres changed with time or from star to star, presumably with the strength of neutron flux in that star or perhaps the temperature. This is a frontier of <i>s</i>-process studies in the 2000s. </p> <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=S-process&action=edit&section=4" 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-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</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 id="CITEREFSuessUrey1956" class="citation journal cs1">Suess, H. E.; Urey, H. C. (1956). "Abundances of the Elements". <i><a href="/wiki/Reviews_of_Modern_Physics" title="Reviews of Modern Physics">Reviews of Modern Physics</a></i>. <b>28</b> (1): 53–74. <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/1956RvMP...28...53S">1956RvMP...28...53S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FRevModPhys.28.53">10.1103/RevModPhys.28.53</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reviews+of+Modern+Physics&rft.atitle=Abundances+of+the+Elements&rft.volume=28&rft.issue=1&rft.pages=53-74&rft.date=1956&rft_id=info%3Adoi%2F10.1103%2FRevModPhys.28.53&rft_id=info%3Abibcode%2F1956RvMP...28...53S&rft.aulast=Suess&rft.aufirst=H.+E.&rft.au=Urey%2C+H.+C.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-Synthesis_of_the_Elements_in_Stars-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-Synthesis_of_the_Elements_in_Stars_2-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBurbidgeBurbidgeFowlerHoyle1957" class="citation journal cs1">Burbidge, E. M.; Burbidge, G. R.; Fowler, W. A.; Hoyle, F. (1957). <a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FRevModPhys.29.547">"Synthesis of the Elements in Stars"</a>. <i><a href="/wiki/Reviews_of_Modern_Physics" title="Reviews of Modern Physics">Reviews of Modern Physics</a></i>. <b>29</b> (4): 547–650. <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/1957RvMP...29..547B">1957RvMP...29..547B</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FRevModPhys.29.547">10.1103/RevModPhys.29.547</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reviews+of+Modern+Physics&rft.atitle=Synthesis+of+the+Elements+in+Stars&rft.volume=29&rft.issue=4&rft.pages=547-650&rft.date=1957&rft_id=info%3Adoi%2F10.1103%2FRevModPhys.29.547&rft_id=info%3Abibcode%2F1957RvMP...29..547B&rft.aulast=Burbidge&rft.aufirst=E.+M.&rft.au=Burbidge%2C+G.+R.&rft.au=Fowler%2C+W.+A.&rft.au=Hoyle%2C+F.&rft_id=https%3A%2F%2Fdoi.org%2F10.1103%252FRevModPhys.29.547&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-CRC-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-CRC_3-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHammond2004" class="citation book cs1">Hammond, C. R. (2004). "The Elements". <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/crchandbookofche81lide"><i>Handbook of Chemistry and Physics</i></a></span> (81st ed.). <a href="/wiki/CRC_Press" title="CRC Press">CRC Press</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8493-0485-9" title="Special:BookSources/978-0-8493-0485-9"><bdi>978-0-8493-0485-9</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=The+Elements&rft.btitle=Handbook+of+Chemistry+and+Physics&rft.edition=81st&rft.pub=CRC+Press&rft.date=2004&rft.isbn=978-0-8493-0485-9&rft.aulast=Hammond&rft.aufirst=C.+R.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fcrchandbookofche81lide&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMoore1951" class="citation journal cs1">Moore, C. E. (1951). "Technetium in the Sun". <i><a href="/wiki/Science_(journal)" title="Science (journal)">Science</a></i>. <b>114</b> (2951): 59–61. <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/1951Sci...114...59M">1951Sci...114...59M</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.114.2951.59">10.1126/science.114.2951.59</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/17782983">17782983</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=Technetium+in+the+Sun&rft.volume=114&rft.issue=2951&rft.pages=59-61&rft.date=1951&rft_id=info%3Apmid%2F17782983&rft_id=info%3Adoi%2F10.1126%2Fscience.114.2951.59&rft_id=info%3Abibcode%2F1951Sci...114...59M&rft.aulast=Moore&rft.aufirst=C.+E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMerrill,_P._W.1952" class="citation journal cs1">Merrill, P. W. (1952). "Technetium in the stars". <i>Science</i>. <b>115</b> (2992): 484.</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=Technetium+in+the+stars&rft.volume=115&rft.issue=2992&rft.pages=484&rft.date=1952&rft.au=Merrill%2C+P.+W.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGeorge_Sivulka2017" class="citation web cs1">George Sivulka (8 March 2017). <a rel="nofollow" class="external text" href="http://large.stanford.edu/courses/2017/ph241/sivulka1/">"An Introduction to the Evidence for Stellar Nucleosynthesis"</a>. Stanford University<span class="reference-accessdate">. Retrieved <span class="nowrap">3 May</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=An+Introduction+to+the+Evidence+for+Stellar+Nucleosynthesis&rft.pub=Stanford+University&rft.date=2017-03-08&rft.au=George+Sivulka&rft_id=http%3A%2F%2Flarge.stanford.edu%2Fcourses%2F2017%2Fph241%2Fsivulka1%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></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="CITEREFClaytonFowlerHullZimmerman1961" class="citation journal cs1">Clayton, D. D.; Fowler, W. A.; Hull, T. E.; Zimmerman, B. A. (1961). "Neutron capture chains in heavy element synthesis". <i><a href="/wiki/Annals_of_Physics" title="Annals of Physics">Annals of Physics</a></i>. <b>12</b> (3): 331–408. <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/1961AnPhy..12..331C">1961AnPhy..12..331C</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0003-4916%2861%2990067-7">10.1016/0003-4916(61)90067-7</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+Physics&rft.atitle=Neutron+capture+chains+in+heavy+element+synthesis&rft.volume=12&rft.issue=3&rft.pages=331-408&rft.date=1961&rft_id=info%3Adoi%2F10.1016%2F0003-4916%2861%2990067-7&rft_id=info%3Abibcode%2F1961AnPhy..12..331C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Fowler%2C+W.+A.&rft.au=Hull%2C+T.+E.&rft.au=Zimmerman%2C+B.+A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFClaytonRassbach1967" class="citation journal cs1">Clayton, D. D.; Rassbach, M. E. (1967). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F149128">"Termination of the <i>s</i>-process"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>148</b>: 69. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1967ApJ...148...69C">1967ApJ...148...69C</a></span>. <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/10.1086%2F149128">10.1086/149128</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=Termination+of+the+s-process&rft.volume=148&rft.pages=69&rft.date=1967&rft_id=info%3Adoi%2F10.1086%2F149128&rft_id=info%3Abibcode%2F1967ApJ...148...69C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Rassbach%2C+M.+E.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F149128&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClayton1968" class="citation book cs1">Clayton, D. D. (1968). "Distribution of neutron-source strengths for the <i>s</i>-process". In Arnett, W. D.; Hansen, C. J.; Truran, J. W.; Cameron, A. G. W. (eds.). <i>Nucleosynthesis</i>. <a href="/wiki/Gordon_and_Breach" class="mw-redirect" title="Gordon and Breach">Gordon and Breach</a>. pp. 225–240.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Distribution+of+neutron-source+strengths+for+the+s-process&rft.btitle=Nucleosynthesis&rft.pages=225-240&rft.pub=Gordon+and+Breach&rft.date=1968&rft.aulast=Clayton&rft.aufirst=D.+D.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFPetersFowlerClayton1972" class="citation journal cs1">Peters, J. G.; Fowler, W. A.; Clayton, D. D. (1972). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F151450">"Weak <i>s</i>-process Irradiations"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>173</b>: 637. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1972ApJ...173..637P">1972ApJ...173..637P</a></span>. <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/10.1086%2F151450">10.1086/151450</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=Weak+s-process+Irradiations&rft.volume=173&rft.pages=637&rft.date=1972&rft_id=info%3Adoi%2F10.1086%2F151450&rft_id=info%3Abibcode%2F1972ApJ...173..637P&rft.aulast=Peters&rft.aufirst=J.+G.&rft.au=Fowler%2C+W.+A.&rft.au=Clayton%2C+D.+D.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F151450&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFClaytonNewman1974" class="citation journal cs1">Clayton, D. D.; Newman, M. J. (1974). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F153082">"<i>s</i>-process Studies: Exact Solution to a Chain Having Two Distinct Cross-Section Values"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>192</b>: 501. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1974ApJ...192..501C">1974ApJ...192..501C</a></span>. <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/10.1086%2F153082">10.1086/153082</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=s-process+Studies%3A+Exact+Solution+to+a+Chain+Having+Two+Distinct+Cross-Section+Values&rft.volume=192&rft.pages=501&rft.date=1974&rft_id=info%3Adoi%2F10.1086%2F153082&rft_id=info%3Abibcode%2F1974ApJ...192..501C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Newman%2C+M.+J.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F153082&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClaytonWard1974" class="citation journal cs1">Clayton, D. D.; Ward, R. A. (1974). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F153175">"<i>s</i>-process Studies: Exact Evaluation of an Exponential Distribution of Exposures"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>193</b>: 397. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1974ApJ...193..397C">1974ApJ...193..397C</a></span>. <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/10.1086%2F153175">10.1086/153175</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=s-process+Studies%3A+Exact+Evaluation+of+an+Exponential+Distribution+of+Exposures&rft.volume=193&rft.pages=397&rft.date=1974&rft_id=info%3Adoi%2F10.1086%2F153175&rft_id=info%3Abibcode%2F1974ApJ...193..397C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Ward%2C+R.+A.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F153175&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWardNewmanClayton1976" class="citation journal cs1">Ward, R. A.; Newman, M. J.; Clayton, D. D. (1976). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F190373">"<i>s</i>-process Studies: Branching and the Time Scale"</a>. <i><a href="/wiki/The_Astrophysical_Journal_Supplement_Series" class="mw-redirect" title="The Astrophysical Journal Supplement Series">The Astrophysical Journal Supplement Series</a></i>. <b>31</b>: 33. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1976ApJS...31...33W">1976ApJS...31...33W</a></span>. <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/10.1086%2F190373">10.1086/190373</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal+Supplement+Series&rft.atitle=s-process+Studies%3A+Branching+and+the+Time+Scale&rft.volume=31&rft.pages=33&rft.date=1976&rft_id=info%3Adoi%2F10.1086%2F190373&rft_id=info%3Abibcode%2F1976ApJS...31...33W&rft.aulast=Ward&rft.aufirst=R.+A.&rft.au=Newman%2C+M.+J.&rft.au=Clayton%2C+D.+D.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F190373&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMacklinGibbons1965" class="citation journal cs1">Macklin, R. L.; Gibbons, J. H. (1965). "Neutron Capture Data at Stellar Temperatures". <i><a href="/wiki/Reviews_of_Modern_Physics" title="Reviews of Modern Physics">Reviews of Modern Physics</a></i>. <b>37</b> (1): 166–176. <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/1965RvMP...37..166M">1965RvMP...37..166M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FRevModPhys.37.166">10.1103/RevModPhys.37.166</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reviews+of+Modern+Physics&rft.atitle=Neutron+Capture+Data+at+Stellar+Temperatures&rft.volume=37&rft.issue=1&rft.pages=166-176&rft.date=1965&rft_id=info%3Adoi%2F10.1103%2FRevModPhys.37.166&rft_id=info%3Abibcode%2F1965RvMP...37..166M&rft.aulast=Macklin&rft.aufirst=R.+L.&rft.au=Gibbons%2C+J.+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFKaeppelerBeerWisshakClayton1982" class="citation journal cs1">Kaeppeler, F.; Beer, H.; Wisshak, K.; Clayton, D. D.; Macklin, R. L.; Ward, R. A. (1982). <a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F160033">"<i>s</i>-process studies in the light of new experimental cross sections"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>257</b>: 821–846. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1982ApJ...257..821K">1982ApJ...257..821K</a></span>. <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/10.1086%2F160033">10.1086/160033</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=s-process+studies+in+the+light+of+new+experimental+cross+sections&rft.volume=257&rft.pages=821-846&rft.date=1982&rft_id=info%3Adoi%2F10.1086%2F160033&rft_id=info%3Abibcode%2F1982ApJ...257..821K&rft.aulast=Kaeppeler&rft.aufirst=F.&rft.au=Beer%2C+H.&rft.au=Wisshak%2C+K.&rft.au=Clayton%2C+D.+D.&rft.au=Macklin%2C+R.+L.&rft.au=Ward%2C+R.+A.&rft_id=https%3A%2F%2Fdoi.org%2F10.1086%252F160033&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-Reifarth2010-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-Reifarth2010_16-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFReifarth2010" class="citation journal cs1">Reifarth, R. (2010). <a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F1742-6596%2F202%2F1%2F012022">"The s-process – overview and selected developments"</a>. <i>Journal of Physics: Conference Series</i>. <b>202</b> (012022). <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/10.1088%2F1742-6596%2F202%2F1%2F012022">10.1088/1742-6596/202/1/012022</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Physics%3A+Conference+Series&rft.atitle=The+s-process+%E2%80%93+overview+and+selected+developments&rft.volume=202&rft.issue=012022&rft.date=2010&rft_id=info%3Adoi%2F10.1088%2F1742-6596%2F202%2F1%2F012022&rft.aulast=Reifarth&rft.aufirst=R.&rft_id=https%3A%2F%2Fdoi.org%2F10.1088%252F1742-6596%252F202%252F1%252F012022&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFBoothroyd2006" class="citation journal cs1">Boothroyd, A. I. (2006). "Heavy elements in stars". <i><a href="/wiki/Science_(journal)" title="Science (journal)">Science</a></i>. <b>314</b> (5806): 1690–1691. <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.1136842">10.1126/science.1136842</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/17170281">17170281</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:116938510">116938510</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=Heavy+elements+in+stars&rft.volume=314&rft.issue=5806&rft.pages=1690-1691&rft.date=2006&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A116938510%23id-name%3DS2CID&rft_id=info%3Apmid%2F17170281&rft_id=info%3Adoi%2F10.1126%2Fscience.1136842&rft.aulast=Boothroyd&rft.aufirst=A.+I.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBussoGallinoWasserburg1999" class="citation journal cs1">Busso, M.; Gallino, R.; Wasserburg, G. J. (1999). <a rel="nofollow" class="external text" href="https://authors.library.caltech.edu/1194/1/BUSaraa99.pdf">"Nucleosynthesis in Asymptotic Giant Branch Stars: Relevance for Galactic Enrichment and Solar System Formation"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/wiki/Annual_Review_of_Astronomy_and_Astrophysics" title="Annual Review of Astronomy and Astrophysics">Annual Review of Astronomy and Astrophysics</a></i>. <b>37</b> (1): 239–309. <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/1999ARA&A..37..239B">1999ARA&A..37..239B</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1146%2Fannurev.astro.37.1.239">10.1146/annurev.astro.37.1.239</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Annual+Review+of+Astronomy+and+Astrophysics&rft.atitle=Nucleosynthesis+in+Asymptotic+Giant+Branch+Stars%3A+Relevance+for+Galactic+Enrichment+and+Solar+System+Formation&rft.volume=37&rft.issue=1&rft.pages=239-309&rft.date=1999&rft_id=info%3Adoi%2F10.1146%2Fannurev.astro.37.1.239&rft_id=info%3Abibcode%2F1999ARA%26A..37..239B&rft.aulast=Busso&rft.aufirst=M.&rft.au=Gallino%2C+R.&rft.au=Wasserburg%2C+G.+J.&rft_id=https%3A%2F%2Fauthors.library.caltech.edu%2F1194%2F1%2FBUSaraa99.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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="CITEREFSrinivasanAnders1978" class="citation journal cs1">Srinivasan, B.; Anders, E. (1978). "Noble Gases in the Murchison Meteorite: Possible Relics of <i>s</i>-process Nucleosynthesis". <i><a href="/wiki/Science_(journal)" title="Science (journal)">Science</a></i>. <b>201</b> (4350): 51–56. <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/1978Sci...201...51S">1978Sci...201...51S</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.201.4350.51">10.1126/science.201.4350.51</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/17777755">17777755</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:21175338">21175338</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=Noble+Gases+in+the+Murchison+Meteorite%3A+Possible+Relics+of+s-process+Nucleosynthesis&rft.volume=201&rft.issue=4350&rft.pages=51-56&rft.date=1978&rft_id=info%3Adoi%2F10.1126%2Fscience.201.4350.51&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A21175338%23id-name%3DS2CID&rft_id=info%3Apmid%2F17777755&rft_id=info%3Abibcode%2F1978Sci...201...51S&rft.aulast=Srinivasan&rft.aufirst=B.&rft.au=Anders%2C+E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" 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"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClaytonWard1978" class="citation journal cs1">Clayton, D. D.; Ward, R. A. (1978). <a rel="nofollow" class="external text" href="http://tigerprints.clemson.edu/cgi/viewcontent.cgi?article=1338&context=physastro_pubs">"<i>s</i>-process studies: Xenon and krypton isotopic abundances"</a>. <i><a href="/wiki/The_Astrophysical_Journal" title="The Astrophysical Journal">The Astrophysical Journal</a></i>. <b>224</b>: 1000. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1978ApJ...224.1000C">1978ApJ...224.1000C</a></span>. <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/10.1086%2F156449">10.1086/156449</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=s-process+studies%3A+Xenon+and+krypton+isotopic+abundances&rft.volume=224&rft.pages=1000&rft.date=1978&rft_id=info%3Adoi%2F10.1086%2F156449&rft_id=info%3Abibcode%2F1978ApJ...224.1000C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Ward%2C+R.+A.&rft_id=http%3A%2F%2Ftigerprints.clemson.edu%2Fcgi%2Fviewcontent.cgi%3Farticle%3D1338%26context%3Dphysastro_pubs&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> <li id="cite_note-Clayton2004-21"><span class="mw-cite-backlink">^ <a href="#cite_ref-Clayton2004_21-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Clayton2004_21-1"><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="CITEREFClaytonNittler2004" class="citation journal cs1">Clayton, D. D.; Nittler, L. R. (2004). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200219012701/https://pdfs.semanticscholar.org/a254/39a457245a227a7e010c2033cac8e17e8306.pdf">"Astrophysics with Presolar Stardust"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/wiki/Annual_Review_of_Astronomy_and_Astrophysics" title="Annual Review of Astronomy and Astrophysics">Annual Review of Astronomy and Astrophysics</a></i>. <b>42</b> (1): 39–78. <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/2004ARA&A..42...39C">2004ARA&A..42...39C</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1146%2Fannurev.astro.42.053102.134022">10.1146/annurev.astro.42.053102.134022</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:96456868">96456868</a>. Archived from <a rel="nofollow" class="external text" href="https://pdfs.semanticscholar.org/a254/39a457245a227a7e010c2033cac8e17e8306.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 2020-02-19.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Annual+Review+of+Astronomy+and+Astrophysics&rft.atitle=Astrophysics+with+Presolar+Stardust&rft.volume=42&rft.issue=1&rft.pages=39-78&rft.date=2004&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A96456868%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1146%2Fannurev.astro.42.053102.134022&rft_id=info%3Abibcode%2F2004ARA%26A..42...39C&rft.aulast=Clayton&rft.aufirst=D.+D.&rft.au=Nittler%2C+L.+R.&rft_id=https%3A%2F%2Fpdfs.semanticscholar.org%2Fa254%2F39a457245a227a7e010c2033cac8e17e8306.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AS-process" class="Z3988"></span></span> </li> </ol></div></div> <div class="navbox-styles"><style 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style="width:1%"><a href="/wiki/Radioactive_decay" title="Radioactive decay">Radioactive decay</a></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/Alpha_decay" title="Alpha decay">Alpha</a></li> <li><a href="/wiki/Beta_decay" title="Beta decay">Beta</a> <ul><li><a href="/wiki/Double_beta_decay" title="Double beta decay">Double</a></li></ul></li> <li><a href="/wiki/Gamma_ray" title="Gamma ray">Gamma radiation</a></li> <li><a href="/wiki/Cluster_decay" title="Cluster decay">Cluster decay</a></li> <li><a href="/wiki/Electron_capture" title="Electron capture">Electron capture</a> <ul><li><a href="/wiki/Double_electron_capture" title="Double electron capture">Double</a></li></ul></li> <li><a href="/wiki/Internal_conversion" title="Internal conversion">Internal conversion</a></li> <li><a href="/wiki/Isomeric_transition" class="mw-redirect" title="Isomeric transition">Isomeric transition</a></li> <li><a href="/wiki/Neutron_emission" title="Neutron emission">Neutron emission</a></li> <li><a href="/wiki/Positron_emission" title="Positron emission">Positron emission</a></li> <li><a href="/wiki/Proton_emission" title="Proton emission">Proton emission</a></li> <li><a href="/wiki/Spontaneous_fission" title="Spontaneous fission">Spontaneous fission</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stellar_nucleosynthesis" title="Stellar nucleosynthesis">Stellar nucleosynthesis</a></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/Deuterium_fusion" title="Deuterium fusion">Deuterium fusion</a></li> <li><a href="/wiki/Lithium_burning" title="Lithium burning">Li burning</a></li> <li><a href="/wiki/Proton%E2%80%93proton_chain" title="Proton–proton chain">Proton–proton chain</a></li> <li><a href="/wiki/CNO_cycle" title="CNO cycle">CNO cycle</a></li> <li><a href="/wiki/Alpha_process" title="Alpha process">α process</a></li> <li><a href="/wiki/Triple-alpha_process" title="Triple-alpha process">Triple-α</a></li> <li><a href="/wiki/Carbon-burning_process" title="Carbon-burning process">C burning</a></li> <li><a href="/wiki/Neon-burning_process" title="Neon-burning process">Ne burning</a></li> <li><a href="/wiki/Oxygen-burning_process" title="Oxygen-burning process">O burning</a></li> <li><a href="/wiki/Silicon-burning_process" title="Silicon-burning process">Si burning</a></li> <li><a href="/wiki/R-process" title="R-process"><i>r</i>-process</a></li> <li><a class="mw-selflink selflink"><i>s</i>-process</a></li> <li><a href="/wiki/P-process" title="P-process">p-process</a></li> <li><a href="/wiki/Rp-process" title="Rp-process">rp-process</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other<br />processes</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/Photodisintegration" title="Photodisintegration">Photodisintegration</a></li> <li><a href="/wiki/Photofission" title="Photofission">Photofission</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Capture</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/Neutron_capture" title="Neutron capture">Neutron capture</a></li> <li><a href="/wiki/Proton_capture" title="Proton capture">Proton capture</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Exchange</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/(n-p)_reaction" title="(n-p) reaction">(n-p) reaction</a></li></ul> </div></td></tr></tbody></table><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" aria-labelledby="Stars" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed 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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Star" title="Template:Star"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Star" title="Template 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<li><a href="/wiki/Young_stellar_object" title="Young stellar object">Young stellar object</a> <ul><li><a href="/wiki/Protostar" title="Protostar">Protostar</a></li> <li><a href="/wiki/Pre-main-sequence_star" title="Pre-main-sequence star">Pre-main-sequence</a></li> <li><a href="/wiki/Herbig_Ae/Be_star" title="Herbig Ae/Be star">Herbig Ae/Be</a></li> <li><a href="/wiki/T_Tauri_star" title="T Tauri star">T Tauri</a></li></ul></li> <li><a href="/wiki/Herbig%E2%80%93Haro_object" title="Herbig–Haro object">Herbig–Haro object</a></li> <li><a href="/wiki/Hayashi_track" title="Hayashi track">Hayashi track</a></li> <li><a href="/wiki/Henyey_track" title="Henyey track">Henyey track</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stellar_evolution" title="Stellar evolution">Evolution</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/Main_sequence" title="Main sequence">Main sequence</a></li> <li><a href="/wiki/Red-giant_branch" title="Red-giant branch">Red-giant branch</a></li> <li><a href="/wiki/Horizontal_branch" title="Horizontal branch">Horizontal branch</a> <ul><li><a href="/wiki/Red_clump" title="Red clump">Red clump</a></li></ul></li> <li><a href="/wiki/Asymptotic_giant_branch" title="Asymptotic giant branch">Asymptotic giant branch</a> <ul><li><a href="/wiki/Post-AGB_star" title="Post-AGB star">post-AGB</a></li> <li><a href="/wiki/Super-AGB_star" title="Super-AGB star">super-AGB</a></li></ul></li> <li><a href="/wiki/Blue_loop" title="Blue loop">Blue loop</a></li> <li><a href="/wiki/Planetary_nebula" title="Planetary nebula">Planetary nebula</a> <ul><li><a href="/wiki/Protoplanetary_nebula" title="Protoplanetary nebula">Protoplanetary</a></li></ul></li> <li><a href="/wiki/Wolf-Rayet_nebula" class="mw-redirect" title="Wolf-Rayet nebula">Wolf-Rayet nebula</a></li> <li><a href="/wiki/PG_1159_star" title="PG 1159 star">PG1159</a></li> <li><a href="/wiki/Dredge-up" title="Dredge-up">Dredge-up</a></li> <li><a href="/wiki/OH/IR_star" title="OH/IR star">OH/IR</a></li> <li><a href="/wiki/Instability_strip" title="Instability strip">Instability strip</a></li> <li><a href="/wiki/Luminous_blue_variable" title="Luminous blue variable">Luminous blue variable</a></li> <li><a href="/wiki/Stellar_population" title="Stellar population">Stellar population</a></li> <li><a href="/wiki/Supernova" title="Supernova">Supernova</a> <ul><li><a href="/wiki/Superluminous_supernova" title="Superluminous supernova">Superluminous</a></li> <li><a href="/wiki/Hypernova" title="Hypernova">Hypernova</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stellar_classification" title="Stellar classification">Classification</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><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/Early-type_star" class="mw-redirect" title="Early-type star">Early</a></li> <li><a href="/wiki/Late-type_star" class="mw-redirect" title="Late-type star">Late</a></li> <li>Main sequence <ul><li><a href="/wiki/O-type_main-sequence_star" title="O-type main-sequence star">O</a></li> <li><a href="/wiki/B-type_main-sequence_star" title="B-type main-sequence star">B</a></li> <li><a href="/wiki/A-type_main-sequence_star" title="A-type main-sequence star">A</a></li> <li><a href="/wiki/F-type_main-sequence_star" title="F-type main-sequence star">F</a></li> <li><a href="/wiki/G-type_main-sequence_star" title="G-type main-sequence star">G</a></li> <li><a href="/wiki/K-type_main-sequence_star" title="K-type main-sequence star">K</a></li> <li><a href="/wiki/Red_dwarf" title="Red dwarf">M</a></li></ul></li> <li><a href="/wiki/Subdwarf" title="Subdwarf">Subdwarf</a> <ul><li><a href="/wiki/Subdwarf_O_star" title="Subdwarf O star">O</a></li> <li><a href="/wiki/Subdwarf_B_star" title="Subdwarf B star">B</a></li></ul></li> <li><a href="/wiki/Wolf%E2%80%93Rayet_star" title="Wolf–Rayet star">WR</a></li> <li><a href="/wiki/OB_star" title="OB star">OB</a></li> <li><a href="/wiki/Subgiant" title="Subgiant">Subgiant</a></li> <li><a href="/wiki/Giant_star" title="Giant star">Giant</a> <ul><li><a href="/wiki/Blue_giant" title="Blue giant">Blue</a></li> <li><a href="/wiki/Red_giant" title="Red giant">Red</a></li> <li><a href="/wiki/Yellow_giant" class="mw-redirect" title="Yellow giant">Yellow</a></li></ul></li> <li><a href="/wiki/Bright_giant" class="mw-redirect" title="Bright giant">Bright giant</a></li> <li><a href="/wiki/Supergiant" title="Supergiant">Supergiant</a> <ul><li><a href="/wiki/Blue_supergiant" title="Blue supergiant">Blue</a></li> <li><a href="/wiki/Red_supergiant" title="Red supergiant">Red</a></li> <li><a href="/wiki/Yellow_supergiant" title="Yellow supergiant">Yellow</a></li></ul></li> <li><a href="/wiki/Hypergiant" title="Hypergiant">Hypergiant</a> <ul><li><a href="/wiki/Yellow_hypergiant" title="Yellow hypergiant">Yellow</a></li></ul></li> <li><a href="/wiki/Carbon_star" title="Carbon star">Carbon</a> <ul><li><a href="/wiki/S-type_star" title="S-type star">S</a></li> <li><a href="/wiki/CN_star" title="CN star">CN</a></li> <li><a href="/wiki/CH_star" title="CH star">CH</a></li></ul></li> <li><a href="/wiki/White_dwarf" title="White dwarf">White dwarf</a></li> <li><a href="/wiki/Chemically_peculiar_star" title="Chemically peculiar star">Chemically peculiar</a> <ul><li><a href="/wiki/Am_star" title="Am star">Am</a></li> <li><a href="/wiki/Ap_and_Bp_stars" title="Ap and Bp stars">Ap/Bp</a></li> <li><a href="/wiki/CEMP_star" title="CEMP star">CEMP</a></li> <li><a href="/wiki/Mercury-manganese_star" title="Mercury-manganese star">HgMn</a></li> <li><a href="/wiki/Helium-weak_star" title="Helium-weak star">He-weak</a></li> <li><a href="/wiki/Barium_star" title="Barium star">Barium</a></li> <li><a href="/wiki/Lambda_Bo%C3%B6tis_star" title="Lambda Boötis star">Lambda Boötis</a></li> <li><a href="/wiki/Lead_star" title="Lead star">Lead</a></li> <li><a href="/wiki/Technetium_star" title="Technetium star">Technetium</a></li></ul></li> <li><a href="/wiki/Be_star" title="Be star">Be</a> <ul><li><a href="/wiki/Shell_star" title="Shell star">Shell</a></li></ul></li> <li><a href="/wiki/B(e)_star" title="B(e) star">B[e]</a></li> <li><a href="/wiki/Helium_star" title="Helium star">Helium</a> <ul><li><a href="/wiki/Extreme_helium_star" title="Extreme helium star">Extreme</a></li></ul></li> <li><a href="/wiki/Blue_straggler" title="Blue straggler">Blue straggler</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Compact_star" class="mw-redirect" title="Compact star">Remnants</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/Compact_star" class="mw-redirect" title="Compact star">Compact star</a></li> <li><a href="/wiki/IRAS_00500%2B6713" title="IRAS 00500+6713">Parker's star</a></li> <li><a href="/wiki/White_dwarf" title="White dwarf">White dwarf</a> <ul><li><a href="/wiki/Helium_planet" title="Helium planet">Helium planet</a></li></ul></li> <li><a href="/wiki/Neutron_star" title="Neutron star">Neutron</a> <ul><li><a href="/wiki/Radio-quiet_neutron_star" title="Radio-quiet neutron star">Radio-quiet</a></li> <li><a href="/wiki/Pulsar" title="Pulsar">Pulsar</a> <ul><li><a href="/wiki/Binary_pulsar" title="Binary pulsar">Binary</a></li> <li><a href="/wiki/X-ray_pulsar" title="X-ray pulsar">X-ray</a></li></ul></li> <li><a href="/wiki/Magnetar" title="Magnetar">Magnetar</a></li></ul></li> <li><a href="/wiki/Stellar_black_hole" title="Stellar black hole">Stellar black hole</a></li> <li><a href="/wiki/X-ray_binary" title="X-ray binary">X-ray binary</a> <ul><li><a href="/wiki/X-ray_burster" title="X-ray burster">Burster</a></li></ul></li> <li><a href="/wiki/Soft_gamma_repeater" title="Soft gamma repeater">SGR</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Hypothetical_star" title="Hypothetical star">Hypothetical</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/Blue_dwarf_(red-dwarf_stage)" title="Blue dwarf (red-dwarf stage)">Blue dwarf</a></li> <li><a href="/wiki/Black_dwarf" title="Black dwarf">Black dwarf</a></li> <li><a href="/wiki/Exotic_star" title="Exotic star">Exotic</a> <ul><li><a href="/wiki/Boson_star" class="mw-redirect" title="Boson star">Boson</a></li> <li><a href="/wiki/Electroweak_star" class="mw-redirect" title="Electroweak star">Electroweak</a></li> <li><a href="/wiki/Strange_star" title="Strange star">Strange</a></li> <li><a href="/wiki/Preon_star" class="mw-redirect" title="Preon star">Preon</a></li> <li><a href="/wiki/Planck_star" title="Planck star">Planck</a></li> <li><a href="/wiki/Dark_star_(dark_matter)" title="Dark star (dark matter)">Dark</a></li> <li><a href="/wiki/Dark-energy_star" title="Dark-energy star">Dark-energy</a></li> <li><a href="/wiki/Quark_star" title="Quark star">Quark</a></li> <li><a href="/wiki/Q_star" title="Q star">Q</a></li></ul></li> <li>Black hole star <ul><li><a href="/wiki/Black_star_(semiclassical_gravity)" title="Black star (semiclassical gravity)">Black</a></li> <li>Hawking</li> <li><a href="/wiki/Quasi-star" title="Quasi-star">Quasi-star</a></li></ul></li> <li><a href="/wiki/Gravastar" title="Gravastar">Gravastar</a></li> <li><a href="/wiki/Thorne%E2%80%93%C5%BBytkow_object" title="Thorne–Żytkow object">Thorne–Żytkow object</a></li> <li><a href="/wiki/Iron_star" title="Iron star">Iron</a></li> <li><a href="/wiki/Blitzar" title="Blitzar">Blitzar</a></li> <li><a href="/wiki/White_hole" title="White hole">White hole</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stellar_nucleosynthesis" title="Stellar nucleosynthesis">Nucleosynthesis</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/Deuterium_fusion" title="Deuterium fusion">Deuterium burning</a></li> <li><a href="/wiki/Lithium_burning" title="Lithium burning">Lithium burning</a></li> <li><a href="/wiki/Proton%E2%80%93proton_chain" title="Proton–proton chain">Proton–proton chain</a></li> <li><a href="/wiki/CNO_cycle" title="CNO cycle">CNO cycle</a></li> <li><a href="/wiki/Helium_flash" title="Helium flash">Helium flash</a></li> <li><a href="/wiki/Triple-alpha_process" title="Triple-alpha process">Triple-alpha process</a></li> <li><a href="/wiki/Alpha_process" title="Alpha process">Alpha process</a></li> <li><a href="/wiki/Carbon-burning_process" title="Carbon-burning process">C burning</a></li> <li><a href="/wiki/Neon-burning_process" title="Neon-burning process">Ne burning</a></li> <li><a href="/wiki/Oxygen-burning_process" title="Oxygen-burning process">O burning</a></li> <li><a href="/wiki/Silicon-burning_process" title="Silicon-burning process">Si burning</a></li> <li><a class="mw-selflink selflink">s-process</a></li> <li><a href="/wiki/R-process" title="R-process">r-process</a></li> <li><a href="/wiki/P-process" title="P-process">p-process</a></li> <li><a href="/wiki/Fusor_(astronomy)" title="Fusor (astronomy)">Fusor</a></li> <li><a href="/wiki/Nova" title="Nova">Nova</a> <ul><li><a href="/wiki/Symbiotic_nova" title="Symbiotic nova">Symbiotic</a></li> <li><a href="/wiki/Nova_remnant" title="Nova remnant">Remnant</a></li> <li><a href="/wiki/Luminous_red_nova" title="Luminous red nova">Luminous red nova</a></li> <li><a href="/wiki/Nova#Recurrent_novae" title="Nova">Recurrent</a></li> <li><a href="/wiki/Micronova" title="Micronova">Micronova</a></li></ul></li> <li><a href="/wiki/Supernova_nucleosynthesis" title="Supernova nucleosynthesis">Supernova</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stellar_structure" title="Stellar structure">Structure</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/Stellar_core" title="Stellar core">Core</a></li> <li><a href="/wiki/Convection_zone" title="Convection zone">Convection zone</a> <ul><li><a href="/wiki/Microturbulence" title="Microturbulence">Microturbulence</a></li> <li><a href="/wiki/Solar-like_oscillations" title="Solar-like oscillations">Oscillations</a></li></ul></li> <li><a href="/wiki/Radiation_zone" class="mw-redirect" title="Radiation zone">Radiation zone</a></li> <li><a href="/wiki/Stellar_atmosphere" title="Stellar atmosphere">Atmosphere</a> <ul><li><a href="/wiki/Photosphere" title="Photosphere">Photosphere</a></li> <li><a href="/wiki/Starspot" title="Starspot">Starspot</a></li> <li><a href="/wiki/Chromosphere" title="Chromosphere">Chromosphere</a></li> <li><a href="/wiki/Stellar_corona" title="Stellar corona">Stellar corona</a></li> <li><a href="/wiki/Alfv%C3%A9n_surface" title="Alfvén surface">Alfvén surface</a></li></ul></li> <li><a href="/wiki/Stellar_wind" title="Stellar wind">Stellar wind</a> <ul><li><a href="/wiki/Stellar-wind_bubble" title="Stellar-wind bubble">Bubble</a></li> <li><a href="/wiki/Bipolar_outflow" title="Bipolar outflow">Bipolar outflow</a></li></ul></li> <li><a href="/wiki/Accretion_disk" title="Accretion disk">Accretion disk</a> <ul><li><a href="/wiki/Protoplanetary_disk" title="Protoplanetary disk">Protoplanetary disk</a></li> <li><a href="/wiki/Proplyd" title="Proplyd">Proplyd</a></li></ul></li> <li><a href="/wiki/Asteroseismology" title="Asteroseismology">Asteroseismology</a> <ul><li><a href="/wiki/Helioseismology" title="Helioseismology">Helioseismology</a></li></ul></li> <li><a href="/wiki/Circumstellar_dust" title="Circumstellar dust">Circumstellar dust</a></li> <li><a href="/wiki/Cosmic_dust" title="Cosmic dust">Cosmic dust</a></li> <li><a href="/wiki/Circumstellar_envelope" title="Circumstellar envelope">Circumstellar envelope</a></li> <li><a href="/wiki/Eddington_luminosity" title="Eddington luminosity">Eddington luminosity</a></li> <li><a href="/wiki/Kelvin%E2%80%93Helmholtz_mechanism" title="Kelvin–Helmholtz mechanism">Kelvin–Helmholtz mechanism</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Properties</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/Stellar_designations_and_names" title="Stellar designations and names">Designation</a></li> <li><a href="/wiki/Stellar_dynamics" title="Stellar dynamics">Dynamics</a></li> <li><a href="/wiki/Effective_temperature" title="Effective temperature">Effective temperature</a></li> <li><a href="/wiki/Luminosity" title="Luminosity">Luminosity</a></li> <li><a href="/wiki/Stellar_kinematics" title="Stellar kinematics">Kinematics</a></li> <li><a href="/wiki/Stellar_magnetic_field" title="Stellar magnetic field">Magnetic field</a></li> <li><a href="/wiki/Absolute_magnitude" title="Absolute magnitude">Absolute magnitude</a></li> <li><a href="/wiki/Stellar_mass" title="Stellar mass">Mass</a></li> <li><a href="/wiki/Metallicity" title="Metallicity">Metallicity</a></li> <li><a href="/wiki/Stellar_rotation" title="Stellar rotation">Rotation</a></li> <li><a href="/wiki/Starlight" title="Starlight">Starlight</a></li> <li><a href="/wiki/Variable_star" title="Variable star">Variable</a></li> <li><a href="/wiki/Photometric_system" title="Photometric system">Photometric system</a></li> <li><a href="/wiki/Color_index" title="Color index">Color index</a></li> <li><a href="/wiki/Hertzsprung%E2%80%93Russell_diagram" title="Hertzsprung–Russell diagram">Hertzsprung–Russell diagram</a></li> <li><a href="/wiki/Color%E2%80%93color_diagram" title="Color–color diagram">Color–color diagram</a></li> <li><a href="/wiki/Str%C3%B6mgren_sphere" title="Strömgren sphere">Strömgren sphere</a></li> <li><a href="/wiki/Kraft_break" title="Kraft break">Kraft break</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Star_system" title="Star system">Star systems</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/Binary_star" title="Binary star">Binary</a> <ul><li><a href="/wiki/Contact_binary" title="Contact binary">Contact</a></li> <li><a href="/wiki/Common_envelope" title="Common envelope">Common envelope</a></li> <li><a href="/wiki/Eclipsing_binary" class="mw-redirect" title="Eclipsing binary">Eclipsing</a></li> <li><a href="/wiki/Symbiotic_binary" title="Symbiotic binary">Symbiotic</a></li></ul></li> <li><a href="/wiki/Star_system#Multiple_star_systems" title="Star system">Multiple</a></li> <li><a href="/wiki/Star_cluster" title="Star cluster">Cluster</a> <ul><li><a href="/wiki/Open_cluster" title="Open cluster">Open</a></li> <li><a href="/wiki/Globular_cluster" title="Globular cluster">Globular</a></li> <li><a href="/wiki/Super_star_cluster" title="Super star cluster">Super</a></li></ul></li> <li><a href="/wiki/Planetary_system" title="Planetary system">Planetary system</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Earth-centric<br />observations</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/Sun" title="Sun">Sun</a> <ul><li><a href="/wiki/Solar_eclipse" title="Solar eclipse">Solar eclipse</a></li> <li><a href="/wiki/Solar_radio_emission" title="Solar radio emission">Solar radio emission</a></li> <li><a href="/wiki/Solar_System" title="Solar System">Solar System</a></li> <li><a href="/wiki/Sunlight" title="Sunlight">Sunlight</a></li></ul></li> <li><a href="/wiki/Pole_star" title="Pole star">Pole star</a></li> <li><a href="/wiki/Circumpolar_star" title="Circumpolar star">Circumpolar</a></li> <li><a href="/wiki/Constellation" title="Constellation">Constellation</a></li> <li><a href="/wiki/Asterism_(astronomy)" title="Asterism (astronomy)">Asterism</a></li> <li><a href="/wiki/Magnitude_(astronomy)" title="Magnitude (astronomy)">Magnitude</a> <ul><li><a href="/wiki/Apparent_magnitude" title="Apparent magnitude">Apparent</a></li> <li><a href="/wiki/Extinction_(astronomy)" title="Extinction (astronomy)">Extinction</a></li> <li><a href="/wiki/Photographic_magnitude" title="Photographic magnitude">Photographic</a></li></ul></li> <li><a href="/wiki/Radial_velocity" title="Radial velocity">Radial velocity</a></li> <li><a href="/wiki/Proper_motion" title="Proper motion">Proper motion</a></li> <li><a href="/wiki/Stellar_parallax" title="Stellar parallax">Parallax</a></li> <li><a href="/wiki/Photometric-standard_star" title="Photometric-standard star">Photometric-standard</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Lists_of_stars" title="Lists of stars">Lists</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/List_of_proper_names_of_stars" title="List of proper names of stars">Proper names</a> <ul><li><a href="/wiki/List_of_Arabic_star_names" title="List of Arabic star names">Arabic</a></li> <li><a href="/wiki/Chinese_star_names" class="mw-redirect" title="Chinese star names">Chinese</a></li></ul></li> <li><a href="/wiki/List_of_star_extremes" title="List of star extremes">Extremes</a> <ul><li><a href="/wiki/List_of_most_massive_stars" title="List of most massive stars">Most massive</a></li> <li><a href="/wiki/List_of_hottest_stars" title="List of hottest stars">Highest temperature</a></li> <li><a href="/wiki/List_of_coolest_stars" title="List of coolest stars">Lowest temperature</a></li> <li><a href="/wiki/List_of_largest_known_stars" class="mw-redirect" title="List of largest known stars">Largest volume</a></li> <li><a href="/wiki/List_of_smallest_known_stars" title="List of smallest known stars">Smallest volume</a></li> <li><a href="/wiki/List_of_brightest_stars" title="List of brightest stars">Brightest</a></li> <li><a href="/wiki/Historical_brightest_stars" title="Historical brightest stars">Historical brightest</a></li> <li><a href="/wiki/List_of_most_luminous_stars" title="List of most luminous stars">Most luminous</a></li> <li><a href="/wiki/List_of_nearest_stars" title="List of nearest stars">Nearest</a> <ul><li><a href="/wiki/List_of_nearest_bright_stars" title="List of nearest bright stars">bright</a></li></ul></li> <li><a href="/wiki/List_of_the_most_distant_astronomical_objects#List_of_most_distant_objects_by_type" title="List of the most distant astronomical objects">Most distant</a></li></ul></li> <li><a href="/wiki/List_of_stars_with_resolved_images" title="List of stars with resolved images">With resolved images</a></li> <li><a href="/wiki/List_of_multiplanetary_systems" title="List of multiplanetary systems">With multiple exoplanets</a></li> <li><a href="/wiki/List_of_brown_dwarfs" title="List of brown dwarfs">Brown dwarfs</a></li> <li><a href="/wiki/List_of_red_dwarfs" title="List of red dwarfs">Red dwarfs</a></li> <li><a href="/wiki/List_of_white_dwarfs" title="List of white dwarfs">White dwarfs</a></li> <li><a href="/wiki/List_of_novae_in_the_Milky_Way_galaxy" title="List of novae in the Milky Way galaxy">Milky Way novae</a></li> <li><a href="/wiki/List_of_supernovae" title="List of supernovae">Supernovae</a> <ul><li><a href="/wiki/List_of_supernova_candidates" title="List of supernova candidates">Candidates</a></li> <li><a href="/wiki/List_of_supernova_remnants" title="List of supernova remnants">Remnants</a></li></ul></li> <li><a href="/wiki/List_of_planetary_nebulae" title="List of planetary nebulae">Planetary nebulae</a></li> <li><a href="/wiki/Timeline_of_stellar_astronomy" title="Timeline of stellar astronomy">Timeline of stellar astronomy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</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/Substellar_object" title="Substellar object">Substellar object</a> <ul><li><a href="/wiki/Brown_dwarf" title="Brown dwarf">Brown dwarf</a> <ul><li><a href="/wiki/Brown-dwarf_desert" title="Brown-dwarf desert">Desert</a></li> <li><a href="/wiki/Sub-brown_dwarf" title="Sub-brown dwarf">Sub</a></li></ul></li> <li><a href="/wiki/Planet" title="Planet">Planet</a></li></ul></li> <li><a href="/wiki/Galactic_year" title="Galactic year">Galactic year</a></li> <li><a href="/wiki/Galaxy" title="Galaxy">Galaxy</a></li> <li><a href="/wiki/Guest_star_(astronomy)" title="Guest star (astronomy)">Guest</a></li> <li><a href="/wiki/Gravity" title="Gravity">Gravity</a></li> <li><a href="/wiki/Intergalactic_star" title="Intergalactic star">Intergalactic</a></li> <li><a href="/wiki/Planet-hosting_stars" class="mw-redirect" title="Planet-hosting stars">Planet-hosting stars</a></li> <li><a href="/wiki/Tidal_disruption_event" title="Tidal disruption event">Tidal disruption event</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" 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