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class="vector-toc-numb">2</span> <span>Caesium-131</span> </div> </a> <ul id="toc-Caesium-131-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Caesium-133" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Caesium-133"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Caesium-133</span> </div> </a> <ul id="toc-Caesium-133-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Caesium-134" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Caesium-134"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Caesium-134</span> </div> </a> <ul id="toc-Caesium-134-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Caesium-135" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Caesium-135"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Caesium-135</span> </div> </a> <ul id="toc-Caesium-135-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Caesium-136" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Caesium-136"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Caesium-136</span> </div> </a> <ul id="toc-Caesium-136-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Caesium-137" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Caesium-137"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Caesium-137</span> </div> </a> <ul id="toc-Caesium-137-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_isotopes_of_caesium" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Other_isotopes_of_caesium"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Other isotopes of caesium</span> </div> </a> <ul id="toc-Other_isotopes_of_caesium-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" 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interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Is%C3%B2tops_del_cesi" title="Isòtops del cesi – Catalan" lang="ca" hreflang="ca" data-title="Isòtops del cesi" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%A6%D0%B5%D0%B7%D0%B8_%D0%B8%D0%B7%D0%BE%D1%82%D0%BE%D0%BF%C4%95%D1%81%D0%B5%D0%BC" title="Цези изотопĕсем – Chuvash" lang="cv" hreflang="cv" data-title="Цези изотопĕсем" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Izotopy_cesia" title="Izotopy cesia – Czech" lang="cs" hreflang="cs" data-title="Izotopy cesia" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Anexo:Is%C3%B3topos_de_cesio" title="Anexo:Isótopos de cesio – Spanish" lang="es" hreflang="es" data-title="Anexo:Isótopos de cesio" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Izotopoj_de_cezio" title="Izotopoj de cezio – Esperanto" lang="eo" hreflang="eo" data-title="Izotopoj de cezio" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%A7%DB%8C%D8%B2%D9%88%D8%AA%D9%88%D9%BE%E2%80%8C%D9%87%D8%A7%DB%8C_%D8%B3%D8%B2%DB%8C%D9%85" title="ایزوتوپ‌های سزیم – Persian" lang="fa" hreflang="fa" data-title="ایزوتوپ‌های سزیم" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Isotopes_du_c%C3%A9sium" title="Isotopes du césium – French" lang="fr" hreflang="fr" data-title="Isotopes du césium" 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/%EC%84%B8%EC%8A%98_%EB%8F%99%EC%9C%84_%EC%9B%90%EC%86%8C" title="세슘 동위 원소 – Korean" lang="ko" hreflang="ko" data-title="세슘 동위 원소" 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/Isotop_sesium" title="Isotop sesium – Indonesian" lang="id" hreflang="id" data-title="Isotop sesium" 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/Isotopi_del_cesio" title="Isotopi del cesio – Italian" lang="it" hreflang="it" data-title="Isotopi del cesio" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/A_c%C3%A9zium_izot%C3%B3pjai" title="A cézium izotópjai – Hungarian" lang="hu" hreflang="hu" data-title="A cézium izotópjai" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%98%D0%B7%D0%BE%D1%82%D0%BE%D0%BF%D0%B8_%D0%BD%D0%B0_%D1%86%D0%B5%D0%B7%D0%B8%D1%83%D0%BC%D0%BE%D1%82" title="Изотопи на цезиумот – Macedonian" lang="mk" hreflang="mk" data-title="Изотопи на цезиумот" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Isotopen_van_cesium" title="Isotopen van cesium – Dutch" lang="nl" hreflang="nl" data-title="Isotopen van cesium" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%BB%E3%82%B7%E3%82%A6%E3%83%A0%E3%81%AE%E5%90%8C%E4%BD%8D%E4%BD%93" title="セシウムの同位体 – Japanese" lang="ja" hreflang="ja" data-title="セシウムの同位体" data-language-autonym="日本語" 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<div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Caesium-131&redirect=no" class="mw-redirect" title="Caesium-131">Caesium-131</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox"><caption class="infobox-title"><span class="nowrap"><a href="/wiki/Isotope" title="Isotope">Isotopes</a> of <a href="/wiki/Caesium" title="Caesium">caesium</a> <style data-mw-deduplicate="TemplateStyles:r886047488">.mw-parser-output .nobold{font-weight:normal}</style><span class="nobold">(<sub>55</sub>Cs)</span></span></caption><tbody><tr><td colspan="2" class="infobox-full-data"> <table class="wikitable" style="text-align: center; vertical-align: middle; width: 100%; border-collapse: collapse; margin: 0; padding: 0;"> <tbody><tr> <th colspan="3">Main isotopes<sup id="cite_ref-NUBASE2020_1-0" class="reference"><a href="#cite_note-NUBASE2020-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </th> <th colspan="2"><a href="/wiki/Radioactive_decay" title="Radioactive decay">Decay</a> </th></tr> <tr> <th> </th> <th style="padding: 0.1em;"><a href="/wiki/Natural_abundance" title="Natural abundance">abundance</a> </th> <th style="padding: 0.1em;"><a href="/wiki/Half-life" title="Half-life">half-life</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold">(<i>t</i><sub>1/2</sub>)</span> </th> <th style="padding: 0.1em;"><a href="/wiki/Radioactive_decay#Types_of_decay" title="Radioactive decay">mode</a> </th> <th style="padding: 0.1em;"><a href="/wiki/Decay_product" title="Decay product">product</a> </th></tr> <tr> <th rowspan="1" style="vertical-align: top;"><sup>131</sup>Cs </th> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: center;"><a href="/wiki/Synthetic_radioisotope" title="Synthetic radioisotope">synth</a> </td> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: right;"><span class="nowrap"><span data-sort-value="7005838079999999999♠"></span>9.7 d</span> </td> <td style="text-align: left; vertical-align: top;"><span style="float: left; font-size: 115%; padding: 0;"><a href="/wiki/Electron_capture" title="Electron capture">ε</a></span><span style="float: right; padding-left: 0.2em;"></span> </td> <td style="text-align: right; vertical-align: middle;"><a href="/wiki/Xenon-131" class="mw-redirect" title="Xenon-131"><sup>131</sup>Xe</a> </td></tr> <tr> <th rowspan="1" style="vertical-align: top;"><sup>133</sup>Cs </th> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: right;">100% </td> <td rowspan="1" colspan="3" style="vertical-align: top; text-align: left;"><a href="/wiki/Stable_isotope" class="mw-redirect" title="Stable isotope">stable</a> </td></tr> <tr> <th rowspan="2" style="vertical-align: top;"><sup>134</sup>Cs </th> <td rowspan="2" colspan="1" style="vertical-align: top; text-align: center;">synth </td> <td rowspan="2" colspan="1" style="vertical-align: top; text-align: right;"><span class="nowrap"><span data-sort-value="7007651601324800000♠"></span>2.0648 y</span> </td> <td style="text-align: left; vertical-align: top;"><span style="float: left; font-size: 115%; padding: 0;">ε</span><span style="float: right; padding-left: 0.2em;"></span> </td> <td style="text-align: right; vertical-align: middle;"><a href="/wiki/Xenon-134" class="mw-redirect" title="Xenon-134"><sup>134</sup>Xe</a> </td></tr> <tr> <td style="text-align: left; vertical-align: top;"><span style="float: left; font-size: 115%; padding: 0;"><a href="/wiki/Beta_minus_decay" class="mw-redirect" title="Beta minus decay">β<sup>−</sup></a></span><span style="float: right; padding-left: 0.2em;"></span> </td> <td style="text-align: right; vertical-align: middle;"><a href="/wiki/Barium-134" class="mw-redirect" title="Barium-134"><sup>134</sup>Ba</a> </td></tr> <tr> <th rowspan="1" style="vertical-align: top;"><sup>135</sup>Cs </th> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: center;"><a href="/wiki/Trace_radioisotope" title="Trace radioisotope">trace</a> </td> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: right;"><span class="nowrap"><span data-sort-value="7013419716080000000♠"></span>1.33<span style="margin-left:0.25em;margin-right:0.15em;">×</span>10<sup>6</sup> y</span> </td> <td style="text-align: left; vertical-align: top;"><span style="float: left; font-size: 115%; padding: 0;">β<sup>−</sup></span><span style="float: right; padding-left: 0.2em;"></span> </td> <td style="text-align: right; vertical-align: middle;"><a href="/wiki/Barium-135" class="mw-redirect" title="Barium-135"><sup>135</sup>Ba</a> </td></tr> <tr> <th rowspan="1" style="vertical-align: top;"><a href="/wiki/Caesium-137" title="Caesium-137"><sup>137</sup>Cs</a> </th> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: center;">synth </td> <td rowspan="1" colspan="1" style="vertical-align: top; text-align: right;"><span class="nowrap"><span data-sort-value="7008947990304000000♠"></span>30.04 y</span><sup id="cite_ref-isotope_2-0" class="reference"><a href="#cite_note-isotope-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </td> <td style="text-align: left; vertical-align: top;"><span style="float: left; font-size: 115%; padding: 0;">β<sup>−</sup></span><span style="float: right; padding-left: 0.2em;"></span> </td> <td style="text-align: right; vertical-align: middle;"><a href="/wiki/Barium-137" class="mw-redirect" title="Barium-137"><sup>137</sup>Ba</a> </td></tr></tbody></table></td></tr><tr><th colspan="2" class="infobox-header" style="background: #e0e0e0;"><a href="/wiki/Standard_atomic_weight" title="Standard atomic weight">Standard atomic weight</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold"><i>A</i><sub>r</sub>°(Cs)</span></th></tr><tr><th scope="row" class="infobox-label"></th><td class="infobox-data"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style><div class="plainlist"><ul><li><span class="nowrap"><span data-sort-value="7002132905451960000♠"></span>132.905<span style="margin-left:.25em;">451</span><span style="margin-left:.25em;">96</span><span style="margin-left:0.3em;margin-right:0.15em;">±</span>0.000<span style="margin-left:.25em;">000</span><span style="margin-left:.25em;">06</span></span><sup id="cite_ref-CIAAW_3-0" class="reference"><a href="#cite_note-CIAAW-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li><li><span class="nowrap"><span data-sort-value="7002132910000000000♠"></span>132.91<span style="margin-left:0.3em;margin-right:0.15em;">±</span>0.01</span> (<a href="/wiki/Standard_atomic_weight#Abridged_atomic_weight" title="Standard atomic weight">abridged</a>)<sup id="cite_ref-CIAAW2021_4-0" class="reference"><a href="#cite_note-CIAAW2021-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li></ul></div></td></tr><tr><td colspan="2" class="infobox-below noprint" style="background: #e8e8e8;"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist 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dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist"><ul><li class="nv-view"><a href="/wiki/Template:Infobox_caesium_isotopes" title="Template:Infobox caesium isotopes"><span title="View this template">view</span></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Infobox_caesium_isotopes" class="mw-redirect" title="Template talk:Infobox caesium isotopes"><span title="Discuss this template">talk</span></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Infobox_caesium_isotopes" title="Special:EditPage/Template:Infobox caesium isotopes"><span title="Edit this template">edit</span></a></li></ul></div></td></tr></tbody></table> <p><a href="/wiki/Caesium" title="Caesium">Caesium</a> (<sub>55</sub>Cs) has 41 known <a href="/wiki/Isotope" title="Isotope">isotopes</a>, ranging in <a href="/wiki/Mass_number" title="Mass number">mass number</a> from 112 to 152. Only one isotope, <sup>133</sup>Cs, is stable.<sup id="cite_ref-:0_5-0" class="reference"><a href="#cite_note-:0-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> The longest-lived <a href="/wiki/Radioisotope" class="mw-redirect" title="Radioisotope">radioisotopes</a> are <sup>135</sup>Cs with a half-life of 1.33 million years, <span style="white-space:nowrap;"><a href="/wiki/Caesium-137" title="Caesium-137"><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">137</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs<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> with a half-life of 30.1671 years and <sup>134</sup>Cs with a half-life of 2.0652 years.<sup id="cite_ref-134Cs-JAEA_6-0" class="reference"><a href="#cite_note-134Cs-JAEA-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> All other isotopes have half-lives less than 2 weeks, most under an hour. </p><p>Beginning in 1945 with the commencement of <a href="/wiki/Nuclear_testing" class="mw-redirect" title="Nuclear testing">nuclear testing</a>, caesium radioisotopes were released into the <a href="/wiki/Earth%27s_atmosphere" class="mw-redirect" title="Earth's atmosphere">atmosphere</a> where caesium is absorbed readily into solution and is returned to the surface of the Earth as a component of <a href="/wiki/Radioactive_fallout" class="mw-redirect" title="Radioactive fallout">radioactive fallout</a>. Once caesium enters the ground water, it is deposited on soil surfaces and removed from the landscape primarily by particle transport. As a result, the input function of these isotopes can be estimated as a function of time. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="List_of_isotopes">List of isotopes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=1" title="Edit section: List of isotopes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><span class="anchor" id="Caesium-111"></span><span class="anchor" id="Caesium-144m1"></span><span class="anchor" id="Caesium-144m2"></span><span class="anchor" id="Caesium-152"></span> </p><p><br /> </p> <table class="wikitable sortable" style="font-size: 85%; white-space: nowrap"> <tbody><tr style="vertical-align: top"> <th rowspan="2">Nuclide<br /><sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>n 1<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="1"><a href="/wiki/Atomic_number" title="Atomic number"><i>Z</i></a> </th> <th rowspan="1"><a href="/wiki/Neutron_number" title="Neutron number"><i>N</i></a> </th> <th rowspan="1"><a href="/wiki/Atomic_mass" title="Atomic mass">Isotopic mass</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold">(<a href="/wiki/Dalton_(unit)" title="Dalton (unit)">Da</a>)</span><sup id="cite_ref-AME2020_II_8-0" class="reference"><a href="#cite_note-AME2020_II-8"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><br /><sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>n 2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-TMS_10-0" class="reference"><a href="#cite_note-TMS-10"><span class="cite-bracket">[</span>n 3<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="2"><a href="/wiki/Half-life" title="Half-life">Half-life</a><sup id="cite_ref-NUBASE2020_1-1" class="reference"><a href="#cite_note-NUBASE2020-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><br /> </th> <th rowspan="2"><a href="/wiki/Decay_mode" class="mw-redirect" title="Decay mode">Decay<br />mode</a><sup id="cite_ref-NUBASE2020_1-2" class="reference"><a href="#cite_note-NUBASE2020-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><br /><sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>n 4<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="2"><a href="/wiki/Decay_product" title="Decay product">Daughter<br />isotope</a><br /><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>n 5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>n 6<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="2"><a href="/wiki/Spin_(particle_physics)" class="mw-redirect" title="Spin (particle physics)">Spin</a> and<br /><a href="/wiki/Parity_(physics)#Nuclei" title="Parity (physics)">parity</a><sup id="cite_ref-NUBASE2020_1-3" class="reference"><a href="#cite_note-NUBASE2020-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><br /><sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>n 7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-TNN_15-0" class="reference"><a href="#cite_note-TNN-15"><span class="cite-bracket">[</span>n 8<span class="cite-bracket">]</span></a></sup> </th> <th rowspan="2"><a href="/wiki/Natural_abundance" title="Natural abundance">Isotopic<br />abundance</a> </th></tr> <tr> <th colspan="3">Excitation energy<sup id="cite_ref-TNN_15-1" class="reference"><a href="#cite_note-TNN-15"><span class="cite-bracket">[</span>n 8<span class="cite-bracket">]</span></a></sup> </th></tr> <tr id="Caesium-112"> <td rowspan="2"><sup>112</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">57 </td> <td rowspan="2">111.95017(12)# </td> <td rowspan="2">490(30) μs </td> <td><a href="/wiki/Proton_emission" title="Proton emission">p</a> (>99.74%) </td> <td><sup>111</sup>Xe </td> <td rowspan="2">1+# </td> <td rowspan="2"> </td></tr> <tr> <td><a href="/wiki/Alpha_decay" title="Alpha decay">α</a> (<0.26%) </td> <td><sup>108</sup>I </td></tr> <tr id="Caesium-113"> <td><sup>113</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">58 </td> <td>112.9444285(92) </td> <td>16.94(9) μs </td> <td>p </td> <td><sup>112</sup>Xe </td> <td>(3/2+) </td> <td> </td></tr> <tr id="Caesium-114"> <td rowspan="4"><sup>114</sup>Cs </td> <td rowspan="4" style="text-align:right">55 </td> <td rowspan="4" style="text-align:right">59 </td> <td rowspan="4">113.941292(91) </td> <td rowspan="4">570(20) ms </td> <td>β<sup>+</sup> (91.1%) </td> <td><sup>114</sup>Xe </td> <td rowspan="4">(1+) </td> <td rowspan="4"> </td></tr> <tr> <td>β<sup>+</sup>, p (8.7%) </td> <td><sup>113</sup>I </td></tr> <tr> <td>β<sup>+</sup>, α (0.19%) </td> <td><sup>110</sup>Te </td></tr> <tr> <td>α (0.018%) </td> <td><sup>110</sup>I </td></tr> <tr id="Caesium-115"> <td rowspan="2"><sup>115</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">60 </td> <td rowspan="2">114.93591(11)# </td> <td rowspan="2">1.4(8) s </td> <td>β<sup>+</sup> (99.93%) </td> <td><sup>115</sup>Xe </td> <td rowspan="2">9/2+# </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>+</sup>, p (0.07%) </td> <td><sup>114</sup>I </td></tr> <tr id="Caesium-116"> <td rowspan="3"><sup>116</sup>Cs </td> <td rowspan="3" style="text-align:right">55 </td> <td rowspan="3" style="text-align:right">61 </td> <td rowspan="3">115.93340(11)# </td> <td rowspan="3">700(40) ms </td> <td>β<sup>+</sup> (99.67%) </td> <td><sup>116</sup>Xe </td> <td rowspan="3">(1+) </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, p (0.28%) </td> <td><sup>115</sup>I </td></tr> <tr> <td>β<sup>+</sup>, α (0.049%) </td> <td><sup>112</sup>Te </td></tr> <tr id="Caesium-116m"> <td rowspan="3" style="text-indent:1em"><sup>116m</sup>Cs<sup id="cite_ref-order_16-0" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="3" colspan="3" style="text-indent:2em">100(60)# keV </td> <td rowspan="3">3.85(13) s </td> <td>β<sup>+</sup> (99.56%) </td> <td><sup>116</sup>Xe </td> <td rowspan="3">(7+) </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, p (0.44%) </td> <td><sup>115</sup>I </td></tr> <tr> <td>β<sup>+</sup>, α (0.0034%) </td> <td><sup>112</sup>Te </td></tr> <tr id="Caesium-117"> <td><sup>117</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">62 </td> <td>116.928617(67) </td> <td>8.4(6) s </td> <td>β<sup>+</sup> </td> <td><sup>117</sup>Xe </td> <td>9/2+# </td> <td> </td></tr> <tr id="Caesium-117m"> <td style="text-indent:1em"><sup>117m</sup>Cs<sup id="cite_ref-order_16-1" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">150(80)# keV </td> <td>6.5(4) s </td> <td>β<sup>+</sup> </td> <td><sup>117</sup>Xe </td> <td>3/2+# </td> <td> </td></tr> <tr id="Caesium-118"> <td rowspan="3"><sup>118</sup>Cs </td> <td rowspan="3" style="text-align:right">55 </td> <td rowspan="3" style="text-align:right">63 </td> <td rowspan="3">117.926560(14) </td> <td rowspan="3">14(2) s </td> <td>β<sup>+</sup> (99.98%) </td> <td><sup>118</sup>Xe </td> <td rowspan="3">2(−)<sup id="cite_ref-zheng2021_17-0" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, p (0.021%) </td> <td><sup>117</sup>I </td></tr> <tr> <td>β<sup>+</sup>, α (0.0012%) </td> <td><sup>114</sup>Te </td></tr> <tr id="Caesium-118m1"> <td rowspan="3" style="text-indent:1em"><sup>118m1</sup>Cs<sup id="cite_ref-zheng2021_17-1" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-order_16-2" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="3" colspan="3" style="text-indent:2em">X keV </td> <td rowspan="3">17(3) s </td> <td>β<sup>+</sup> (99.98%) </td> <td><sup>118</sup>Xe </td> <td rowspan="3">(7−) </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, p (0.021%) </td> <td><sup>117</sup>I </td></tr> <tr> <td>β<sup>+</sup>, α (0.0012%) </td> <td><sup>114</sup>Te </td></tr> <tr id="Caesium-118m2"> <td style="text-indent:1em"><sup>118m2</sup>Cs<sup id="cite_ref-zheng2021_17-2" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-order_16-3" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">Y keV </td> <td> </td> <td> </td> <td> </td> <td>(6+) </td> <td> </td></tr> <tr id="Caesium-118m3"> <td style="text-indent:1em"><sup>118m3</sup>Cs<sup id="cite_ref-zheng2021_17-3" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-order_16-4" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">65.9 keV </td> <td> </td> <td>IT </td> <td><sup>118</sup>Cs </td> <td>(3−) </td> <td> </td></tr> <tr id="Caesium-118m4"> <td style="text-indent:1em"><sup>118m4</sup>Cs<sup id="cite_ref-zheng2021_17-4" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">125.9+X keV </td> <td>550(60) ns </td> <td>IT </td> <td><sup>118m1</sup>Cs </td> <td>(7+) </td> <td> </td></tr> <tr id="Caesium-118m5"> <td style="text-indent:1em"><sup>118m5</sup>Cs<sup id="cite_ref-zheng2021_17-5" class="reference"><a href="#cite_note-zheng2021-17"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">195.2+X keV </td> <td><500 ns </td> <td>IT </td> <td><sup>118m4</sup>Cs </td> <td>(8+) </td> <td> </td></tr> <tr id="Caesium-119"> <td rowspan="2"><sup>119</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">64 </td> <td rowspan="2">118.9223 77(15) </td> <td rowspan="2">43.0(2) s </td> <td>β<sup>+</sup> </td> <td><sup>119</sup>Xe </td> <td rowspan="2">9/2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>+</sup>, α (<2×10<sup>−6</sup>%) </td> <td><sup>115</sup>Te </td></tr> <tr id="Caesium-119m"> <td style="text-indent:1em"><sup>119m</sup>Cs<sup id="cite_ref-order_16-5" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td colspan="3" style="text-indent:2em">50(30)# keV </td> <td>30.4(1) s </td> <td>β<sup>+</sup> </td> <td><sup>119</sup>Xe </td> <td>3/2+ </td> <td> </td></tr> <tr id="Caesium-120"> <td rowspan="3"><sup>120</sup>Cs </td> <td rowspan="3" style="text-align:right">55 </td> <td rowspan="3" style="text-align:right">65 </td> <td rowspan="3">119.920677(11) </td> <td rowspan="3">60.4(6) s </td> <td>β<sup>+</sup> </td> <td><sup>120</sup>Xe </td> <td rowspan="3">2+ </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, α (<2×10<sup>−5</sup>%) </td> <td><sup>116</sup>Te </td></tr> <tr> <td>β<sup>+</sup>, p (<7×10<sup>−6</sup>%) </td> <td><sup>119</sup>I </td></tr> <tr id="Caesium-120m"> <td rowspan="3" style="text-indent:1em"><sup>120m</sup>Cs<sup id="cite_ref-order_16-6" class="reference"><a href="#cite_note-order-16"><span class="cite-bracket">[</span>n 9<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="3" colspan="3" style="text-indent:2em">100(60)# keV </td> <td rowspan="3">57(6) s </td> <td>β<sup>+</sup> </td> <td><sup>120</sup>Xe </td> <td rowspan="3">(7−) </td> <td rowspan="3"> </td></tr> <tr> <td>β<sup>+</sup>, α (<2×10<sup>−5</sup>%) </td> <td><sup>116</sup>Te </td></tr> <tr> <td>β<sup>+</sup>, p (<7×10<sup>−6</sup>%) </td> <td><sup>119</sup>I </td></tr> <tr id="Caesium-121"> <td><sup>121</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">66 </td> <td>120.917227(15) </td> <td>155(4) s </td> <td>β<sup>+</sup> </td> <td><sup>121</sup>Xe </td> <td>3/2+ </td> <td> </td></tr> <tr id="Caesium-121m"> <td rowspan="2" style="text-indent:1em"><sup>121m</sup>Cs </td> <td rowspan="2" colspan="3" style="text-indent:2em">68.5(3) keV </td> <td rowspan="2">122(3) s </td> <td>β<sup>+</sup> (83%) </td> <td><sup>121</sup>Xe </td> <td rowspan="2">9/2+ </td> <td rowspan="2"> </td></tr> <tr> <td><a href="/wiki/Isomeric_transition" class="mw-redirect" title="Isomeric transition">IT</a> (17%) </td> <td><sup>121</sup>Cs </td></tr> <tr id="Caesium-122"> <td rowspan="2"><sup>122</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">67 </td> <td rowspan="2">121.916108(36) </td> <td rowspan="2">21.18(19) s </td> <td>β<sup>+</sup> </td> <td><sup>122</sup>Xe </td> <td rowspan="2">1+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>+</sup>, α (<2×10<sup>−7</sup>%) </td> <td><sup>118</sup>Te </td></tr> <tr id="Caesium-122m1"> <td style="text-indent:1em"><sup>122m1</sup>Cs </td> <td colspan="3" style="text-indent:2em">45.87(12) keV </td> <td>>1 μs </td> <td>IT </td> <td><sup>122</sup>Cs </td> <td>3+ </td> <td> </td></tr> <tr id="Caesium-122m2"> <td style="text-indent:1em"><sup>122m2</sup>Cs </td> <td colspan="3" style="text-indent:2em">140(30) keV </td> <td>3.70(11) min </td> <td>β<sup>+</sup> </td> <td><sup>122</sup>Xe </td> <td>8− </td> <td> </td></tr> <tr id="Caesium-122m3"> <td style="text-indent:1em"><sup>122m3</sup>Cs </td> <td colspan="3" style="text-indent:2em">127.07(16) keV </td> <td>360(20) ms </td> <td>IT </td> <td><sup>122</sup>Cs </td> <td>5− </td> <td> </td></tr> <tr id="Caesium-123"> <td><sup>123</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">68 </td> <td>122.912996(13) </td> <td>5.88(3) min </td> <td>β<sup>+</sup> </td> <td><sup>123</sup>Xe </td> <td>1/2+ </td> <td> </td></tr> <tr id="Caesium-123m1"> <td style="text-indent:1em"><sup>123m1</sup>Cs </td> <td colspan="3" style="text-indent:2em">156.27(5) keV </td> <td>1.64(12) s </td> <td>IT </td> <td><sup>123</sup>Cs </td> <td>11/2− </td> <td> </td></tr> <tr id="Caesium-123m2"> <td style="text-indent:1em"><sup>123m2</sup>Cs </td> <td colspan="3" style="text-indent:2em">252(6) keV </td> <td>114(5) ns </td> <td>IT </td> <td><sup>123</sup>Cs </td> <td>(9/2+) </td> <td> </td></tr> <tr id="Caesium-124"> <td><sup>124</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">69 </td> <td>123.9122474(98) </td> <td>30.9(4) s </td> <td>β<sup>+</sup> </td> <td><i><b><sup>124</sup>Xe</b></i> </td> <td>1+ </td> <td> </td></tr> <tr id="Caesium-124m"> <td rowspan="2" style="text-indent:1em"><sup>124m</sup>Cs </td> <td rowspan="2" colspan="3" style="text-indent:2em">462.63(14) keV </td> <td rowspan="2">6.41(7) s </td> <td>IT (99.89%) </td> <td><sup>124</sup>Cs </td> <td rowspan="2">(7)+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>+</sup> (0.11%) </td> <td><i><b><sup>124</sup>Xe</b></i> </td></tr> <tr id="Caesium-125"> <td><sup>125</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">70 </td> <td>124.9097260(83) </td> <td>44.35(29) min </td> <td>β<sup>+</sup> </td> <td><sup>125</sup>Xe </td> <td>1/2+ </td> <td> </td></tr> <tr id="Caesium-125m"> <td style="text-indent:1em"><sup>125m</sup>Cs </td> <td colspan="3" style="text-indent:2em">266.1(11) keV </td> <td>900(30) ms </td> <td>IT </td> <td><sup>125</sup>Cs </td> <td>(11/2−) </td> <td> </td></tr> <tr id="Caesium-126"> <td><sup>126</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">71 </td> <td>125.909446(11) </td> <td>1.64(2) min </td> <td>β<sup>+</sup> </td> <td><b><sup>126</sup>Xe</b> </td> <td>1+ </td> <td> </td></tr> <tr id="Caesium-126m1"> <td style="text-indent:1em"><sup>126m1</sup>Cs </td> <td colspan="3" style="text-indent:2em">273.0(7) keV </td> <td>~1 μs </td> <td>IT </td> <td><sup>126</sup>Cs </td> <td>(4−) </td> <td> </td></tr> <tr id="Caesium-126m2"> <td style="text-indent:1em"><sup>126m2</sup>Cs </td> <td colspan="3" style="text-indent:2em">596.1(11) keV </td> <td>171(14) μs </td> <td>IT </td> <td><sup>126</sup>Cs </td> <td>8−# </td> <td> </td></tr> <tr id="Caesium-127"> <td><sup>127</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">72 </td> <td>126.9074175(60) </td> <td>6.25(10) h </td> <td>β<sup>+</sup> </td> <td><sup>127</sup>Xe </td> <td>1/2+ </td> <td> </td></tr> <tr id="Caesium-127m"> <td style="text-indent:1em"><sup>127m</sup>Cs </td> <td colspan="3" style="text-indent:2em">452.23(21) keV </td> <td>55(3) μs </td> <td>IT </td> <td><sup>127</sup>Cs </td> <td>(11/2)− </td> <td> </td></tr> <tr id="Caesium-128"> <td><sup>128</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">73 </td> <td>127.9077485(57) </td> <td>3.640(14) min </td> <td>β<sup>+</sup> </td> <td><b><sup>128</sup>Xe</b> </td> <td>1+ </td> <td> </td></tr> <tr id="Caesium-129"> <td><sup>129</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">74 </td> <td>128.9060659(49) </td> <td>32.06(6) h </td> <td>β<sup>+</sup> </td> <td><b><sup>129</sup>Xe</b> </td> <td>1/2+ </td> <td> </td></tr> <tr id="Caesium-129m"> <td style="text-indent:1em"><sup>129m</sup>Cs </td> <td colspan="3" style="text-indent:2em">575.40(14) keV </td> <td>718(21) ns </td> <td>IT </td> <td><sup>127</sup>Cs </td> <td>(11/2−) </td> <td> </td></tr> <tr id="Caesium-130"> <td rowspan="2"><sup>130</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">75 </td> <td rowspan="2">129.9067093(90) </td> <td rowspan="2">29.21(4) min </td> <td>β<sup>+</sup> (98.4%) </td> <td><b><sup>130</sup>Xe</b> </td> <td rowspan="2">1+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup> (1.6%) </td> <td><i><b><sup>130</sup>Ba</b></i> </td></tr> <tr id="Caesium-130m"> <td rowspan="2" style="text-indent:1em"><sup>130m</sup>Cs </td> <td rowspan="2" colspan="3" style="text-indent:2em">163.25(11) keV </td> <td rowspan="2">3.46(6) min </td> <td>IT (99.84%) </td> <td><sup>130</sup>Cs </td> <td rowspan="2">5− </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>+</sup> (0.16%) </td> <td><b><sup>130</sup>Xe</b> </td></tr> <tr> <td><sup>131</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">76 </td> <td>130.90546846(19) </td> <td>9.689(16) d </td> <td><a href="/wiki/Electron_capture" title="Electron capture">EC</a> </td> <td><b><sup>131</sup>Xe</b> </td> <td>5/2+ </td> <td> </td></tr> <tr id="Caesium-132"> <td rowspan="2"><sup>132</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">77 </td> <td rowspan="2">131.9064378(11) </td> <td rowspan="2">6.480(6) d </td> <td>β<sup>+</sup> (98.13%) </td> <td><b><sup>132</sup>Xe</b> </td> <td rowspan="2">2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup> (1.87%) </td> <td><b><sup>132</sup>Ba</b> </td></tr> <tr> <td><sup>133</sup>Cs<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>n 10<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-FP_19-0" class="reference"><a href="#cite_note-FP-19"><span class="cite-bracket">[</span>n 11<span class="cite-bracket">]</span></a></sup> </td> <td style="text-align:right">55 </td> <td style="text-align:right">78 </td> <td>132.905451958(8) </td> <td colspan="3" align="center"><b>Stable</b> </td> <td>7/2+ </td> <td>1.0000 </td></tr> <tr> <td rowspan="2"><sup>134</sup>Cs<sup id="cite_ref-FP_19-1" class="reference"><a href="#cite_note-FP-19"><span class="cite-bracket">[</span>n 11<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">79 </td> <td rowspan="2">133.906718501(17) </td> <td rowspan="2">2.0650(4) y </td> <td>β<sup>−</sup> </td> <td><b><sup>134</sup>Ba</b> </td> <td rowspan="2">4+ </td> <td rowspan="2"> </td></tr> <tr> <td>EC (3.0×10<sup>−4</sup>%) </td> <td><b><sup>134</sup>Xe</b> </td></tr> <tr id="Caesium-134m"> <td style="text-indent:1em"><sup>134m</sup>Cs </td> <td colspan="3" style="text-indent:2em">138.7441(26) keV </td> <td>2.912(2) h </td> <td>IT </td> <td><sup>134</sup>Cs </td> <td>8− </td> <td> </td></tr> <tr> <td><sup>135</sup>Cs<sup id="cite_ref-FP_19-2" class="reference"><a href="#cite_note-FP-19"><span class="cite-bracket">[</span>n 11<span class="cite-bracket">]</span></a></sup> </td> <td style="text-align:right">55 </td> <td style="text-align:right">80 </td> <td>134.90597691(39) </td> <td>1.33(19)×10<sup>6</sup> y </td> <td>β<sup>−</sup> </td> <td><b><sup>135</sup>Ba</b> </td> <td>7/2+ </td> <td> </td></tr> <tr id="Caesium-135m"> <td style="text-indent:1em"><sup>135m</sup>Cs </td> <td colspan="3" style="text-indent:2em">1632.9(15) keV </td> <td>53(2) min </td> <td>IT </td> <td><sup>135</sup>Cs </td> <td>19/2− </td> <td> </td></tr> <tr> <td><sup>136</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">81 </td> <td>135.9073114(20) </td> <td>13.01(5) d </td> <td>β<sup>−</sup> </td> <td><b><sup>136</sup>Ba</b> </td> <td>5+ </td> <td> </td></tr> <tr id="Caesium-136m"> <td rowspan="2" style="text-indent:1em"><sup>136m</sup>Cs </td> <td rowspan="2" colspan="3" style="text-indent:2em">517.9(1) keV </td> <td rowspan="2">17.5(2) s </td> <td>β<sup>−</sup>? </td> <td><b><sup>136</sup>Ba</b> </td> <td rowspan="2">8− </td> <td rowspan="2"> </td></tr> <tr> <td>IT? </td> <td><sup>136</sup>Cs </td></tr> <tr> <td rowspan="2"><a href="/wiki/Caesium-137" title="Caesium-137"><sup>137</sup>Cs</a><sup id="cite_ref-FP_19-3" class="reference"><a href="#cite_note-FP-19"><span class="cite-bracket">[</span>n 11<span class="cite-bracket">]</span></a></sup> </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">82 </td> <td rowspan="2">136.90708930(32) </td> <td rowspan="2">30.04(4) y </td> <td>β<sup>−</sup> (94.70%)<sup id="cite_ref-137cs-decaymode_20-0" class="reference"><a href="#cite_note-137cs-decaymode-20"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </td> <td><sup>137m</sup>Ba </td> <td rowspan="2">7/2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup> (5.30%)<sup id="cite_ref-137cs-decaymode_20-1" class="reference"><a href="#cite_note-137cs-decaymode-20"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </td> <td><b><sup>137</sup>Ba</b> </td></tr> <tr id="Caesium-138"> <td><sup>138</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">83 </td> <td>137.9110171(98) </td> <td>33.5(2) min </td> <td>β<sup>−</sup> </td> <td><b><sup>138</sup>Ba</b> </td> <td>3− </td> <td> </td></tr> <tr id="Caesium-138m"> <td rowspan="2" style="text-indent:1em"><sup>138m</sup>Cs </td> <td rowspan="2" colspan="3" style="text-indent:2em">79.9(3) keV </td> <td rowspan="2">2.91(10) min </td> <td>IT (81%) </td> <td><sup>138</sup>Cs </td> <td rowspan="2">6− </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup> (19%) </td> <td><b><sup>138</sup>Ba</b> </td></tr> <tr id="Caesium-139"> <td><sup>139</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">84 </td> <td>138.9133638(34) </td> <td>9.27(5) min </td> <td>β<sup>−</sup> </td> <td><sup>139</sup>Ba </td> <td>7/2+ </td> <td> </td></tr> <tr id="Caesium-140"> <td><sup>140</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">85 </td> <td>139.9172837(88) </td> <td>63.7(3) s </td> <td>β<sup>−</sup> </td> <td><sup>140</sup>Ba </td> <td>1− </td> <td> </td></tr> <tr id="Caesium-140m"> <td style="text-indent:1em"><sup>140m</sup>Cs </td> <td colspan="3" style="text-indent:2em">13.931(21) keV </td> <td>471(51) ns </td> <td>IT </td> <td><sup>140</sup>Cs </td> <td>(2)− </td> <td> </td></tr> <tr id="Caesium-141"> <td rowspan="2"><sup>141</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">86 </td> <td rowspan="2">140.9200453(99) </td> <td rowspan="2">24.84(16) s </td> <td>β<sup>−</sup> (99.97%) </td> <td><sup>141</sup>Ba </td> <td rowspan="2">7/2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, <a href="/wiki/Neutron_emission" title="Neutron emission">n</a> (0.0342%) </td> <td><sup>140</sup>Ba </td></tr> <tr id="Caesium-142"> <td rowspan="2"><sup>142</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">87 </td> <td rowspan="2">141.9242995(76) </td> <td rowspan="2">1.687(10) s </td> <td>β<sup>−</sup> (99.91%) </td> <td><sup>142</sup>Ba </td> <td rowspan="2">0− </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (0.089%) </td> <td><sup>141</sup>Ba </td></tr> <tr id="Caesium-143"> <td rowspan="2"><sup>143</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">88 </td> <td rowspan="2">142.9273473(81) </td> <td rowspan="2">1.802(8) s </td> <td>β<sup>−</sup> (98.38%) </td> <td><sup>143</sup>Ba </td> <td rowspan="2">3/2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (1.62%) </td> <td><sup>142</sup>Ba </td></tr> <tr id="Caesium-144"> <td rowspan="2"><sup>144</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">89 </td> <td rowspan="2">143.932075(22) </td> <td rowspan="2">994(6) ms </td> <td>β<sup>−</sup> (97.02%) </td> <td><sup>144</sup>Ba </td> <td rowspan="2">1− </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (2.98%) </td> <td><sup>143</sup>Ba </td></tr> <tr id="Caesium-144m"> <td style="text-indent:1em"><sup>144m</sup>Cs </td> <td colspan="3" style="text-indent:2em">92.2(5) keV </td> <td>1.1(1) μs </td> <td>IT </td> <td><sup>144</sup>Cs </td> <td>(4−) </td> <td> </td></tr> <tr id="Caesium-145"> <td rowspan="2"><sup>145</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">90 </td> <td rowspan="2">144.9355289(97) </td> <td rowspan="2">582(4) ms </td> <td>β<sup>−</sup> (87.2%) </td> <td><sup>145</sup>Ba </td> <td rowspan="2">3/2+ </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (12.8%) </td> <td><sup>144</sup>Ba </td></tr> <tr id="Caesium-145m"> <td style="text-indent:1em"><sup>145m</sup>Cs </td> <td colspan="3" style="text-indent:2em">762.9(4) keV </td> <td>0.5(1) μs </td> <td>IT </td> <td><sup>145</sup>Cs </td> <td>13/2# </td> <td> </td></tr> <tr id="Caesium-146"> <td rowspan="2"><sup>146</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">91 </td> <td rowspan="2">145.9406219(31) </td> <td rowspan="2">321.6(9) ms </td> <td>β<sup>−</sup> (85.8%) </td> <td><sup>146</sup>Ba </td> <td rowspan="2">1− </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (14.2%) </td> <td><sup>145</sup>Ba </td></tr> <tr id="Caesium-146m"> <td style="text-indent:1em"><sup>146m</sup>Cs </td> <td colspan="3" style="text-indent:2em">46.7(1) keV </td> <td>1.25(5) μs </td> <td>IT </td> <td><sup>146</sup>Cs </td> <td>4−# </td> <td> </td></tr> <tr id="Caesium-147"> <td rowspan="2"><sup>147</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">92 </td> <td rowspan="2">146.9442615(90) </td> <td rowspan="2">230.5(9) ms </td> <td>β<sup>−</sup> (71.5%) </td> <td><sup>147</sup>Ba </td> <td rowspan="2">(3/2+) </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (28.5%) </td> <td><sup>146</sup>Ba </td></tr> <tr id="Caesium-147m"> <td style="text-indent:1em"><sup>147m</sup>Cs </td> <td colspan="3" style="text-indent:2em">701.4(4) keV </td> <td>190(20) ns </td> <td>IT </td> <td><sup>147</sup>Cs </td> <td>13/2# </td> <td> </td></tr> <tr id="Caesium-148"> <td rowspan="2"><sup>148</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">93 </td> <td rowspan="2">147.949639(14) </td> <td rowspan="2">151.8(10) ms </td> <td>β<sup>−</sup> (71.3%) </td> <td><sup>148</sup>Ba </td> <td rowspan="2">(2−) </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (28.7%) </td> <td><sup>147</sup>Ba </td></tr> <tr id="Caesium-148m"> <td style="text-indent:1em"><sup>148m</sup>Cs </td> <td colspan="3" style="text-indent:2em">45.2(1) keV </td> <td>4.8(2) μs </td> <td>IT </td> <td><sup>148</sup>Cs </td> <td>4−# </td> <td> </td></tr> <tr id="Caesium-149"> <td rowspan="2"><sup>149</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">94 </td> <td rowspan="2">148.95352(43)# </td> <td rowspan="2">112.3(25) ms </td> <td>β<sup>−</sup> (75%) </td> <td><sup>149</sup>Ba </td> <td rowspan="2">3/2+# </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (25%) </td> <td><sup>148</sup>Ba </td></tr> <tr id="Caesium-150"> <td rowspan="2"><sup>150</sup>Cs </td> <td rowspan="2" style="text-align:right">55 </td> <td rowspan="2" style="text-align:right">95 </td> <td rowspan="2">149.95902(43)# </td> <td rowspan="2">81.0(26) ms </td> <td>β<sup>−</sup> (~56%) </td> <td><sup>150</sup>Ba </td> <td rowspan="2">(2−) </td> <td rowspan="2"> </td></tr> <tr> <td>β<sup>−</sup>, n (~44%) </td> <td><sup>149</sup>Ba </td></tr> <tr id="Caesium-151"> <td><sup>151</sup>Cs </td> <td style="text-align:right">55 </td> <td style="text-align:right">96 </td> <td>150.96320(54)# </td> <td>59(19) ms </td> <td>β<sup>−</sup> </td> <td><sup>151</sup>Ba </td> <td>3/2+# </td> <td> </td></tr> <tr> <th colspan="20" style="text-align:right; line-height:85%;"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold"><i>This table header & footer:</i> <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"><ul><li class="nv-view"><a href="/wiki/Template:Isotopes_table" title="Template:Isotopes table"><span title="View this template">view</span></a></li></ul></div></span> </th></tr></tbody></table> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><sup>m</sup>Cs –  Excited <a href="/wiki/Nuclear_isomer" title="Nuclear isomer">nuclear isomer</a>.</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">( ) –  Uncertainty (1<i>σ</i>) is given in concise form in parentheses after the corresponding last digits.</span> </li> <li id="cite_note-TMS-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-TMS_10-0">^</a></b></span> <span class="reference-text"># –  Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).</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"> Modes of decay: <table style="margin-left:1.5em;"> <tbody><tr style="line-height: 1.1em; vertical-align: top"> <td>EC:</td> <td><a href="/wiki/Electron_capture" title="Electron capture">Electron capture</a> <p><br /> </p> </td></tr> <tr style="line-height: 1.1em; vertical-align: top"> <td>IT:</td> <td><a href="/wiki/Isomeric_transition" class="mw-redirect" title="Isomeric transition">Isomeric transition</a> </td></tr> <tr style="line-height: 1.1em; vertical-align: top"> <td>n:</td> <td><a href="/wiki/Neutron_emission" title="Neutron emission">Neutron emission</a> </td></tr> <tr style="line-height: 1.1em; vertical-align: top"> <td>p:</td> <td><a href="/wiki/Proton_emission" title="Proton emission">Proton emission</a> </td></tr></tbody></table></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"><i><b>Bold italics symbol</b></i> as daughter –  Daughter product is nearly stable.</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"><b>Bold symbol</b> as daughter –  Daughter product is stable.</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">( ) spin value –  Indicates spin with weak assignment arguments.</span> </li> <li id="cite_note-TNN-15"><span class="mw-cite-backlink">^ <a href="#cite_ref-TNN_15-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-TNN_15-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"># –  Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).</span> </li> <li id="cite_note-order-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-order_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-order_16-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-order_16-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-order_16-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-order_16-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-order_16-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-order_16-6"><sup><i><b>g</b></i></sup></a></span> <span class="reference-text">Order of ground state and isomer is uncertain.</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">Used to define the <a href="/wiki/Second" title="Second">second</a></span> </li> <li id="cite_note-FP-19"><span class="mw-cite-backlink">^ <a href="#cite_ref-FP_19-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-FP_19-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-FP_19-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-FP_19-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a href="/wiki/Fission_product" class="mw-redirect" title="Fission product">Fission product</a></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="Caesium-131">Caesium-131</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=2" title="Edit section: Caesium-131"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Caesium-131, introduced in 2004 for <a href="/wiki/Brachytherapy" title="Brachytherapy">brachytherapy</a> by <a href="/wiki/IsoRay" title="IsoRay">Isoray</a>,<sup id="cite_ref-131Cs-Isoray_21-0" class="reference"><a href="#cite_note-131Cs-Isoray-21"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> has a <a href="/wiki/Half-life" title="Half-life">half-life</a> of 9.7 days and 30.4 keV energy. </p> <div class="mw-heading mw-heading2"><h2 id="Caesium-133">Caesium-133</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=3" title="Edit section: Caesium-133"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Caesium-133 is the only stable <a href="/wiki/Isotope" title="Isotope">isotope</a> of caesium. The <a href="/wiki/SI_base_unit" title="SI base unit">SI base unit</a> of time, the <a href="/wiki/Second" title="Second">second</a>, is defined by a <a href="/wiki/Caesium_standard" title="Caesium standard">specific caesium-133 transition</a>. Since 1967, the official definition of a second is: </p> <style data-mw-deduplicate="TemplateStyles:r1244412712">.mw-parser-output .templatequote{overflow:hidden;margin:1em 0;padding:0 32px}.mw-parser-output .templatequotecite{line-height:1.5em;text-align:left;margin-top:0}@media(min-width:500px){.mw-parser-output .templatequotecite{padding-left:1.6em}}</style><blockquote class="templatequote"><p>The second, symbol s, is defined by taking the fixed numerical value of the caesium frequency, <span class="texhtml">Δ<i>ν</i><sub>Cs</sub></span>, the unperturbed ground-state hyperfine transition frequency of the caesium-133 atom,<sup id="cite_ref-133Cs-SI_22-0" class="reference"><a href="#cite_note-133Cs-SI-22"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> to be <span class="nowrap"><span data-sort-value="7009919263177000000♠"></span>9<span style="margin-left:.25em;">192</span><span style="margin-left:.25em;">631</span><span style="margin-left:.25em;">770</span></span> <a href="/wiki/Hz" class="mw-redirect" title="Hz">Hz</a>, which is equal to s<sup>−1</sup>. </p></blockquote> <div class="mw-heading mw-heading2"><h2 id="Caesium-134">Caesium-134</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=4" title="Edit section: Caesium-134"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Caesium-134 has a <a href="/wiki/Half-life" title="Half-life">half-life</a> of 2.0652 years. It is produced both directly (at a very small yield because <sup>134</sup>Xe is stable) as a <a href="/wiki/Fission_product" class="mw-redirect" title="Fission product">fission product</a> and via <a href="/wiki/Neutron_capture" title="Neutron capture">neutron capture</a> from nonradioactive <sup>133</sup>Cs (neutron capture <a href="/wiki/Neutron_cross-section" class="mw-redirect" title="Neutron cross-section">cross section</a> 29 <a href="/wiki/Barn_(unit)" title="Barn (unit)">barns</a>), which is a common fission product. Caesium-134 is not produced via <a href="/wiki/Beta_decay" title="Beta decay">beta decay</a> of other fission product <a href="/wiki/Nuclides" class="mw-redirect" title="Nuclides">nuclides</a> of mass 134 since beta decay stops at stable <sup>134</sup>Xe. It is also not produced by <a href="/wiki/Nuclear_weapons" class="mw-redirect" title="Nuclear weapons">nuclear weapons</a> because <sup>133</sup>Cs is created by beta decay of original fission products only long after the nuclear explosion is over. </p><p>The combined yield of <sup>133</sup>Cs and <sup>134</sup>Cs is given as 6.7896%. The proportion between the two will change with continued neutron irradiation. <sup>134</sup>Cs also captures neutrons with a cross section of 140 barns, becoming long-lived radioactive <sup>135</sup>Cs. </p><p>Caesium-134 undergoes <a href="/wiki/Beta_decay" title="Beta decay">beta decay</a> (β<sup>−</sup>), producing <a href="/wiki/Isotopes_of_barium" title="Isotopes of barium"><sup>134</sup>Ba</a> directly and emitting on average 2.23 <a href="/wiki/Gamma_ray" title="Gamma ray">gamma ray</a> photons (mean energy 0.698 <a href="/wiki/MeV" class="mw-redirect" title="MeV">MeV</a>).<sup id="cite_ref-134Cs-JAEA_6-1" class="reference"><a href="#cite_note-134Cs-JAEA-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Caesium-135">Caesium-135</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=5" title="Edit section: Caesium-135"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable sortable" style="clear:right; float:right; max-width:27em; margin:0.5em 0 0.5em 1em; text-align:right;"> <caption style="background-color:#FF6666; padding:0.2em 0.4em;"><style data-mw-deduplicate="TemplateStyles:r1045256916">.mw-parser-output .navbar-header{text-align:center;position:relative;white-space:nowrap}.mw-parser-output .navbar-header .navbar{position:absolute;right:0;top:0;margin:0 5px}</style><div class="navbar-header"><a href="/wiki/Long-lived_fission_product" title="Long-lived fission product">Long-lived fission products</a><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:Long-lived_fission_products" title="Template:Long-lived fission products"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Long-lived_fission_products" title="Template talk:Long-lived fission products"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Long-lived_fission_products" title="Special:EditPage/Template:Long-lived fission products"><abbr title="Edit this template">e</abbr></a></li></ul></div></div> </caption> <tbody><tr> <th>Nuclide </th> <th><a href="/wiki/Halflife" class="mw-redirect" title="Halflife"><i>t</i><sub><style data-mw-deduplicate="TemplateStyles:r1154941027">'"`UNIQ--templatestyles-0000004D-QINU`"'</style><span class="frac"><span class="num">1</span>⁄<span class="den">2</span></span></sub></a> </th> <th><a href="/wiki/Fission_product_yield" title="Fission product yield">Yield</a> </th> <th><a href="/wiki/Decay_energy" title="Decay energy"><i>Q</i></a><sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>a 1<span class="cite-bracket">]</span></a></sup> </th> <th><a href="/wiki/Decay_mode" class="mw-redirect" title="Decay mode">βγ</a> </th></tr> <tr> <th> </th> <th><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold">(<a href="/wiki/Megaannum" class="mw-redirect" title="Megaannum">Ma</a>)</span> </th> <th><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold">(%)</span><sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>a 2<span class="cite-bracket">]</span></a></sup> </th> <th><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886047488" /><span class="nobold">(<a href="/wiki/Kiloelectronvolt" class="mw-redirect" title="Kiloelectronvolt">keV</a>)</span> </th> <th> </th></tr> <tr> <td><a href="/wiki/Technetium-99" title="Technetium-99"><sup>99</sup>Tc</a> </td> <td>0.211</td> <td>6.1385</td> <td>294 </td> <td style="text-align:left;">β </td></tr> <tr> <td><a href="/wiki/Tin-126" class="mw-redirect" title="Tin-126"><sup>126</sup>Sn</a> </td> <td>0.230</td> <td>0.1084</td> <td>4050<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>a 3<span class="cite-bracket">]</span></a></sup> </td> <td style="text-align:left;">β<b>γ</b> </td></tr> <tr> <td><a href="/wiki/Selenium-79" title="Selenium-79"><sup>79</sup>Se</a> </td> <td>0.327</td> <td>0.0447</td> <td>151 </td> <td style="text-align:left;">β </td></tr> <tr> <td><a href="/wiki/Caesium-135" class="mw-redirect" title="Caesium-135"><sup>135</sup>Cs</a> </td> <td>1.33<span class="nowrap"> </span></td> <td>6.9110<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>a 4<span class="cite-bracket">]</span></a></sup></td> <td>269 </td> <td style="text-align:left;">β </td></tr> <tr> <td><a href="/wiki/Zirconium-93" class="mw-redirect" title="Zirconium-93"><sup>93</sup>Zr</a> </td> <td>1.53<span class="nowrap"> </span></td> <td>5.4575</td> <td>91 </td> <td style="text-align:left;">βγ </td></tr> <tr> <td><a href="/wiki/Palladium-107" class="mw-redirect" title="Palladium-107"><sup>107</sup>Pd</a> </td> <td>6.5<span class="nowrap">  </span></td> <td>1.2499</td> <td>33 </td> <td style="text-align:left;">β </td></tr> <tr> <td><a href="/wiki/Iodine-129" title="Iodine-129"><sup>129</sup>I</a> </td> <td>16.14<span class="nowrap">  </span></td> <td>0.8410</td> <td>194 </td> <td style="text-align:left;">βγ </td></tr> <tr class="sortbottom"> <td colspan="5" style="text-align:left;"><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"><ol class="references"> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text">Decay energy is split among <a href="/wiki/Beta_particle" title="Beta particle">β</a>, <a href="/wiki/Neutrino" title="Neutrino">neutrino</a>, and <a href="/wiki/Gamma_ray" title="Gamma ray">γ</a> if any.</span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text">Per 65 thermal neutron fissions of <a href="/wiki/Uranium-235" title="Uranium-235"><sup>235</sup>U</a> and 35 of <a href="/wiki/Plutonium-239" title="Plutonium-239"><sup>239</sup>Pu</a>.</span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text">Has decay energy 380 keV, but its decay product <sup>126</sup>Sb has decay energy 3.67 MeV.</span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text">Lower in thermal reactors because <a href="/wiki/Xenon-135" title="Xenon-135"><sup>135</sup>Xe</a>, its predecessor, <a href="/wiki/Neutron_poison" title="Neutron poison">readily absorbs neutrons</a>.</span> </li> </ol></div></div> </td></tr></tbody></table> <p>Caesium-135 is a mildly <a href="/wiki/Radioactive" class="mw-redirect" title="Radioactive">radioactive</a> isotope of caesium with a half-life of 1.33 million years. It decays via emission of a low-energy beta particle into the stable isotope barium-135. Caesium-135 is one of the seven <a href="/wiki/Long-lived_fission_product" title="Long-lived fission product">long-lived fission products</a> and the only alkaline one. In most types of <a href="/wiki/Nuclear_reprocessing" title="Nuclear reprocessing">nuclear reprocessing</a>, it stays with the <a href="/wiki/Medium-lived_fission_products" class="mw-redirect" title="Medium-lived fission products">medium-lived fission products</a> (including <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">137</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs</span> which can only be separated from <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs</span> via <a href="/wiki/Isotope_separation" title="Isotope separation">isotope separation</a>) rather than with other long-lived fission products. Except in the <a href="/wiki/Molten_salt_reactor" class="mw-redirect" title="Molten salt reactor">Molten salt reactor</a>, where <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs</span> is created as a completely separate stream outside the fuel (after the decay of bubble-separated <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs</span>). The low <a href="/wiki/Decay_energy" title="Decay energy">decay energy</a>, lack of <a href="/wiki/Gamma_radiation" class="mw-redirect" title="Gamma radiation">gamma radiation</a>, and long half-life of <sup>135</sup>Cs make this isotope much less hazardous than <a href="/wiki/Caesium-137" title="Caesium-137"><sup>137</sup>Cs</a> or <sup>134</sup>Cs. </p><p>Its precursor <a href="/wiki/Xenon-135" title="Xenon-135"><sup>135</sup>Xe</a> has a high <a href="/wiki/Fission_product_yield" title="Fission product yield">fission product yield</a> (e.g., 6.3333% for <a href="/wiki/Uranium-235" title="Uranium-235"><sup>235</sup>U</a> and <a href="/wiki/Thermal_neutron" class="mw-redirect" title="Thermal neutron">thermal neutrons</a>) but also has the highest known <a href="/wiki/Thermal_neutron" class="mw-redirect" title="Thermal neutron">thermal neutron</a> capture cross section of any nuclide. Because of this, much of the <sup>135</sup>Xe produced in current <a href="/wiki/Thermal_reactor" class="mw-redirect" title="Thermal reactor">thermal reactors</a> (as much as >90% at steady-state full power)<sup id="cite_ref-Groh2004_27-0" class="reference"><a href="#cite_note-Groh2004-27"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> will be converted to extremely long-lived (half-life on the order of 10<sup>21</sup> years) <span class="chemf nowrap"><a href="/wiki/Xenon-136" class="mw-redirect" title="Xenon-136"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">136</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Xe</a></span> before it can decay to <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Cs</span> despite the relatively short half life of <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Xe</span>. Little or no <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Xe</span> will be destroyed by neutron capture after a reactor shutdown, or in a <a href="/wiki/Molten_salt_reactor" class="mw-redirect" title="Molten salt reactor">molten salt reactor</a> that continuously removes xenon from its fuel, a <a href="/wiki/Fast_neutron_reactor" class="mw-redirect" title="Fast neutron reactor">fast neutron reactor</a>, or a nuclear weapon. The <a href="/wiki/Xenon_pit" class="mw-redirect" title="Xenon pit">xenon pit</a> is a phenomenon of excess neutron absorption through <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Xe</span> buildup in the reactor after a reduction in power or a shutdown and is often managed by letting the <span class="chemf nowrap"><span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:0.5em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">135</sup><br /><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline"></sub></span></span>Xe</span> decay away to a level at which neutron flux can be safely controlled via <a href="/wiki/Control_rod" title="Control rod">control rods</a> again. </p><p>A nuclear reactor will also produce much smaller amounts of <sup>135</sup>Cs from the nonradioactive fission product <sup>133</sup>Cs by successive neutron capture to <sup>134</sup>Cs and then <sup>135</sup>Cs. </p><p>The thermal neutron capture cross section and <a href="/wiki/Resonance_integral" class="mw-redirect" title="Resonance integral">resonance integral</a> of <sup>135</sup>Cs are <span class="nowrap">8.3 ± 0.3</span> and <span class="nowrap">38.1 ± 2.6 <a href="/wiki/Barn_(unit)" title="Barn (unit)">barns</a></span> respectively.<sup id="cite_ref-Hatsukawa1999_28-0" class="reference"><a href="#cite_note-Hatsukawa1999-28"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> Disposal of <sup>135</sup>Cs by <a href="/wiki/Nuclear_transmutation" title="Nuclear transmutation">nuclear transmutation</a> is difficult, because of the low cross section as well as because neutron irradiation of mixed-isotope fission caesium produces more <sup>135</sup>Cs from stable <sup>133</sup>Cs. In addition, the intense medium-term radioactivity of <sup>137</sup>Cs makes handling of nuclear waste difficult.<sup id="cite_ref-Ohki_29-0" class="reference"><a href="#cite_note-Ohki-29"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <ul><li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110429095603/http://www.ead.anl.gov/pub/doc/cesium.pdf">ANL factsheet</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Caesium-136">Caesium-136</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=6" title="Edit section: Caesium-136"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Caesium-136 has a half-life of 13.01 days.<sup id="cite_ref-:0_5-1" class="reference"><a href="#cite_note-:0-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> It is produced both directly (at a very small yield because <sup>136</sup>Xe is <a href="/wiki/Beta-decay_stable_isobars" title="Beta-decay stable isobars">beta-stable</a>) as a fission product and via neutron capture from long-lived <sup>135</sup>Cs,<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> which is a common fission product. It is also not produced by nuclear weapons because <sup>135</sup>Cs is created by beta decay of original fission products only long after the nuclear explosion is over. Caesium-136 undergoes beta decay (β−), producing <sup>136</sup>Ba directly.<sup id="cite_ref-:0_5-2" class="reference"><a href="#cite_note-:0-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Caesium-137">Caesium-137</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=7" title="Edit section: Caesium-137"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Caesium-137" title="Caesium-137">Caesium-137</a></div> <p>Caesium-137, with a half-life of 30.17 years, is one of the two principal <a href="/wiki/Medium-lived_fission_product" class="mw-redirect" title="Medium-lived fission product">medium-lived fission products</a>, along with <a href="/wiki/Strontium-90" title="Strontium-90"><sup>90</sup>Sr</a>, which are responsible for most of the <a href="/wiki/Radioactivity" class="mw-redirect" title="Radioactivity">radioactivity</a> of <a href="/wiki/Spent_nuclear_fuel" title="Spent nuclear fuel">spent nuclear fuel</a> after several years of cooling, up to several hundred years after use. It constitutes most of the radioactivity still left from the <a href="/wiki/Chernobyl_disaster" title="Chernobyl disaster">Chernobyl accident</a> and is a major health concern for decontaminating land near the <a href="/wiki/Fukushima_Daiichi_nuclear_disaster" class="mw-redirect" title="Fukushima Daiichi nuclear disaster">Fukushima</a> nuclear power plant.<sup id="cite_ref-137Cs-Normile_31-0" class="reference"><a href="#cite_note-137Cs-Normile-31"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> <sup>137</sup>Cs beta decays to barium-137m (a short-lived <a href="/wiki/Nuclear_isomer" title="Nuclear isomer">nuclear isomer</a>) then to nonradioactive <a href="/wiki/Barium-137" class="mw-redirect" title="Barium-137">barium-137</a>. Caesium-137 does not emit gamma radiation directly, all observed radiation is due to the daughter isotope barium-137m. </p><p><sup>137</sup>Cs has a very low rate of neutron capture and cannot yet be feasibly disposed of in this way unless advances in neutron beam collimation (not otherwise achievable by magnetic fields), uniquely available only from within <a href="/wiki/Muon_catalyzed_fusion" class="mw-redirect" title="Muon catalyzed fusion">muon catalyzed fusion</a> experiments (not in the other forms of <a href="/wiki/Nuclear_transmutation#Artificial_transmutation_of_nuclear_waste" title="Nuclear transmutation">Accelerator Transmutation of Nuclear Waste</a>) enables production of neutrons at high enough intensity to offset and overcome these low capture rates; until then, therefore, <sup>137</sup>Cs must simply be allowed to decay. </p><p><sup>137</sup>Cs has been used as a <a href="/wiki/Flow_tracer" title="Flow tracer">tracer</a> in hydrologic studies, analogous to the use of <a href="/wiki/Tritium" title="Tritium"><sup>3</sup>H</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Other_isotopes_of_caesium">Other isotopes of caesium</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Isotopes_of_caesium&action=edit&section=8" title="Edit section: Other isotopes of caesium"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The other isotopes have half-lives from a few days to fractions of a second. Almost all caesium produced from nuclear fission comes from beta decay of originally more neutron-rich fission products, passing through <a href="/wiki/Isotopes_of_iodine" title="Isotopes of iodine">isotopes of iodine</a> then <a href="/wiki/Isotopes_of_xenon" title="Isotopes of xenon">isotopes of xenon</a>. Because these elements are volatile and can diffuse through nuclear fuel or air, caesium is often created far from the original site of fission. </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=Isotopes_of_caesium&action=edit&section=9" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626" /><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-NUBASE2020-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-NUBASE2020_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-NUBASE2020_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-NUBASE2020_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-NUBASE2020_1-3"><sup><i><b>d</b></i></sup></a></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="CITEREFKondevWangHuangNaimi2021" class="citation journal cs1">Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). <a rel="nofollow" class="external text" href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf">"The NUBASE2020 evaluation of nuclear properties"</a> <span class="cs1-format">(PDF)</span>. <i>Chinese Physics C</i>. <b>45</b> (3): 030001. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F1674-1137%2Fabddae">10.1088/1674-1137/abddae</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Chinese+Physics+C&rft.atitle=The+NUBASE2020+evaluation+of+nuclear+properties&rft.volume=45&rft.issue=3&rft.pages=030001&rft.date=2021&rft_id=info%3Adoi%2F10.1088%2F1674-1137%2Fabddae&rft.aulast=Kondev&rft.aufirst=F.+G.&rft.au=Wang%2C+M.&rft.au=Huang%2C+W.+J.&rft.au=Naimi%2C+S.&rft.au=Audi%2C+G.&rft_id=https%3A%2F%2Fwww-nds.iaea.org%2Famdc%2Fame2020%2FNUBASE2020.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span> </span> </li> <li id="cite_note-isotope-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-isotope_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.nist.gov/pml/data/halflife.cfm">"NIST Radionuclide Half-Life Measurements"</a>. <i><a href="/wiki/NIST" class="mw-redirect" title="NIST">NIST</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">2011-03-13</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=NIST&rft.atitle=NIST+Radionuclide+Half-Life+Measurements&rft_id=http%3A%2F%2Fwww.nist.gov%2Fpml%2Fdata%2Fhalflife.cfm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-CIAAW-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-CIAAW_3-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.ciaaw.org/caesium.htm">"Standard Atomic Weights: Caesium"</a>. <a href="/wiki/Commission_on_Isotopic_Abundances_and_Atomic_Weights" title="Commission on Isotopic Abundances and Atomic Weights">CIAAW</a>. 2013.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Standard+Atomic+Weights%3A+Caesium&rft.pub=CIAAW&rft.date=2013&rft_id=https%3A%2F%2Fwww.ciaaw.org%2Fcaesium.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-CIAAW2021-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-CIAAW2021_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFProhaskaIrrgeherBenefieldBöhlke2022" class="citation journal cs1">Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). <a rel="nofollow" class="external text" href="https://www.degruyter.com/document/doi/10.1515/pac-2019-0603/html">"Standard atomic weights of the elements 2021 (IUPAC Technical Report)"</a>. <i>Pure and Applied Chemistry</i>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1515%2Fpac-2019-0603">10.1515/pac-2019-0603</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1365-3075">1365-3075</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Pure+and+Applied+Chemistry&rft.atitle=Standard+atomic+weights+of+the+elements+2021+%28IUPAC+Technical+Report%29&rft.date=2022-05-04&rft_id=info%3Adoi%2F10.1515%2Fpac-2019-0603&rft.issn=1365-3075&rft.aulast=Prohaska&rft.aufirst=Thomas&rft.au=Irrgeher%2C+Johanna&rft.au=Benefield%2C+Jacqueline&rft.au=B%C3%B6hlke%2C+John+K.&rft.au=Chesson%2C+Lesley+A.&rft.au=Coplen%2C+Tyler+B.&rft.au=Ding%2C+Tiping&rft.au=Dunn%2C+Philip+J.+H.&rft.au=Gr%C3%B6ning%2C+Manfred&rft.au=Holden%2C+Norman+E.&rft.au=Meijer%2C+Harro+A.+J.&rft_id=https%3A%2F%2Fwww.degruyter.com%2Fdocument%2Fdoi%2F10.1515%2Fpac-2019-0603%2Fhtml&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-:0-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-:0_5-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.nndc.bnl.gov/">"NNDC | National Nuclear Data Center"</a>. <i>www.nndc.bnl.gov</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2025-02-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.nndc.bnl.gov&rft.atitle=NNDC+%7C+National+Nuclear+Data+Center&rft_id=https%3A%2F%2Fwww.nndc.bnl.gov%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-134Cs-JAEA-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-134Cs-JAEA_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-134Cs-JAEA_6-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160304100452/http://c-navi.jaea.go.jp/en/background/remediation-following-major-radiation-accidents/characteristics-of-caesium-134-and-caesium-137.html">"Characteristics of Caesium-134 and Caesium-137"</a>. Japan Atomic Energy Agency. Archived from <a rel="nofollow" class="external text" href="http://c-navi.jaea.go.jp/en/background/remediation-following-major-radiation-accidents/characteristics-of-caesium-134-and-caesium-137.html">the original</a> on 2016-03-04<span class="reference-accessdate">. Retrieved <span class="nowrap">2014-10-23</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Characteristics+of+Caesium-134+and+Caesium-137&rft.pub=Japan+Atomic+Energy+Agency&rft_id=http%3A%2F%2Fc-navi.jaea.go.jp%2Fen%2Fbackground%2Fremediation-following-major-radiation-accidents%2Fcharacteristics-of-caesium-134-and-caesium-137.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-AME2020_II-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-AME2020_II_8-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFWangHuangKondevAudi2021" class="citation journal cs1">Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". <i>Chinese Physics C</i>. <b>45</b> (3): 030003. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F1674-1137%2Fabddaf">10.1088/1674-1137/abddaf</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Chinese+Physics+C&rft.atitle=The+AME+2020+atomic+mass+evaluation+%28II%29.+Tables%2C+graphs+and+references%2A&rft.volume=45&rft.issue=3&rft.pages=030003&rft.date=2021&rft_id=info%3Adoi%2F10.1088%2F1674-1137%2Fabddaf&rft.aulast=Wang&rft.aufirst=Meng&rft.au=Huang%2C+W.J.&rft.au=Kondev%2C+F.G.&rft.au=Audi%2C+G.&rft.au=Naimi%2C+S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-zheng2021-17"><span class="mw-cite-backlink">^ <a href="#cite_ref-zheng2021_17-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-zheng2021_17-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-zheng2021_17-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-zheng2021_17-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-zheng2021_17-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-zheng2021_17-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFZhengPetracheZhangAstier2021" class="citation journal cs1">Zheng, K. K.; Petrache, C. M.; Zhang, Z. H.; Astier, A.; Lv, B. F.; Greenlees, P. T.; Grahn, T.; Julin, R.; Juutinen, S.; Luoma, M.; Ojala, J.; Pakarinen, J.; Partanen, J.; Rahkila, P.; Ruotsalainen, P.; Sandzelius, M.; Sarén, J.; Tann, H.; Uusitalo, J.; Zimba, G.; Cederwall, B.; Aktas, ö.; Ertoprak, A.; Zhang, W.; Guo, S.; Liu, M. L.; Zhou, X. H.; Kuti, I.; Nyakó, B. M.; Sohler, D.; Timár, J.; Andreoiu, C.; Doncel, M.; Joss, D. T.; Page, R. D. (21 October 2021). <a rel="nofollow" class="external text" href="https://www.researchgate.net/publication/355502046_Rich_band_structure_and_multiple_long-lived_isomers_in_the_odd-odd_Cs_118_nucleus">"Rich band structure and multiple long-lived isomers in the odd-odd Cs 118 nucleus"</a>. <i>Physical Review C</i>. <b>104</b> (4). <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%2FPhysRevC.104.044325">10.1103/PhysRevC.104.044325</a><span class="reference-accessdate">. Retrieved <span class="nowrap">29 December</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Physical+Review+C&rft.atitle=Rich+band+structure+and+multiple+long-lived+isomers+in+the+odd-odd+Cs+118+nucleus&rft.volume=104&rft.issue=4&rft.date=2021-10-21&rft_id=info%3Adoi%2F10.1103%2FPhysRevC.104.044325&rft.aulast=Zheng&rft.aufirst=K.+K.&rft.au=Petrache%2C+C.+M.&rft.au=Zhang%2C+Z.+H.&rft.au=Astier%2C+A.&rft.au=Lv%2C+B.+F.&rft.au=Greenlees%2C+P.+T.&rft.au=Grahn%2C+T.&rft.au=Julin%2C+R.&rft.au=Juutinen%2C+S.&rft.au=Luoma%2C+M.&rft.au=Ojala%2C+J.&rft.au=Pakarinen%2C+J.&rft.au=Partanen%2C+J.&rft.au=Rahkila%2C+P.&rft.au=Ruotsalainen%2C+P.&rft.au=Sandzelius%2C+M.&rft.au=Sar%C3%A9n%2C+J.&rft.au=Tann%2C+H.&rft.au=Uusitalo%2C+J.&rft.au=Zimba%2C+G.&rft.au=Cederwall%2C+B.&rft.au=Aktas%2C+%C3%B6.&rft.au=Ertoprak%2C+A.&rft.au=Zhang%2C+W.&rft.au=Guo%2C+S.&rft.au=Liu%2C+M.+L.&rft.au=Zhou%2C+X.+H.&rft.au=Kuti%2C+I.&rft.au=Nyak%C3%B3%2C+B.+M.&rft.au=Sohler%2C+D.&rft.au=Tim%C3%A1r%2C+J.&rft.au=Andreoiu%2C+C.&rft.au=Doncel%2C+M.&rft.au=Joss%2C+D.+T.&rft.au=Page%2C+R.+D.&rft_id=https%3A%2F%2Fwww.researchgate.net%2Fpublication%2F355502046_Rich_band_structure_and_multiple_long-lived_isomers_in_the_odd-odd_Cs_118_nucleus&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-137cs-decaymode-20"><span class="mw-cite-backlink">^ <a href="#cite_ref-137cs-decaymode_20-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-137cs-decaymode_20-1"><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="CITEREFBrowneTuli2007" class="citation journal cs1">Browne, E.; Tuli, J.K. (October 2007). "Nuclear Data Sheets for A = 137". <i>Nuclear Data Sheets</i>. <b>108</b> (10): <span class="nowrap">2173–</span>2318. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.nds.2007.09.002">10.1016/j.nds.2007.09.002</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nuclear+Data+Sheets&rft.atitle=Nuclear+Data+Sheets+for+A+%3D+137&rft.volume=108&rft.issue=10&rft.pages=%3Cspan+class%3D%22nowrap%22%3E2173-%3C%2Fspan%3E2318&rft.date=2007-10&rft_id=info%3Adoi%2F10.1016%2Fj.nds.2007.09.002&rft.aulast=Browne&rft.aufirst=E.&rft.au=Tuli%2C+J.K.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-131Cs-Isoray-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-131Cs-Isoray_21-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFIsoray" class="citation web cs1">Isoray. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190630105241/https://isoray.com/why-cesium-131/">"Why Cesium-131"</a>. Archived from <a rel="nofollow" class="external text" href="https://isoray.com/why-cesium-131/">the original</a> on 2019-06-30<span class="reference-accessdate">. Retrieved <span class="nowrap">2017-12-05</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Why+Cesium-131&rft.au=Isoray&rft_id=https%3A%2F%2Fisoray.com%2Fwhy-cesium-131%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-133Cs-SI-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-133Cs-SI_22-0">^</a></b></span> <span class="reference-text">Although the phase used here is more terse than in the previous definition, it still has the same meaning. This is made clear in the 9th SI Brochure, which almost immediately after the definition on p. 130 states: "The effect of this definition is that the second is equal to the duration of <span class="nowrap"><span data-sort-value="7009919263177000000♠"></span>9<span style="margin-left:.25em;">192</span><span style="margin-left:.25em;">631</span><span style="margin-left:.25em;">770</span></span> periods of the radiation corresponding to the transition between the two hyperfine levels of the unperturbed ground state of the <sup>133</sup>Cs atom."</span> </li> <li id="cite_note-Groh2004-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-Groh2004_27-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFJohn_L._Groh2004" class="citation web cs1">John L. Groh (2004). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110610131653/http://canteach.candu.org/library/20041204.pdf">"Supplement to Chapter 11 of Reactor Physics Fundamentals"</a> <span class="cs1-format">(PDF)</span>. CANTEACH project. Archived from <a rel="nofollow" class="external text" href="http://canteach.candu.org/library/20041204.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 10 June 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">14 May</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Supplement+to+Chapter+11+of+Reactor+Physics+Fundamentals&rft.pub=CANTEACH+project&rft.date=2004&rft.au=John+L.+Groh&rft_id=http%3A%2F%2Fcanteach.candu.org%2Flibrary%2F20041204.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-Hatsukawa1999-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-Hatsukawa1999_28-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFHatsukawaShinoharaHata1999" class="citation journal cs1">Hatsukawa, Y.; Shinohara, N; Hata, K.; et al. (1999). "Thermal neutron cross section and resonance integral of the reaction of135Cs(n,γ)136Cs: Fundamental data for the transmutation of nuclear waste". <i>Journal of Radioanalytical and Nuclear Chemistry</i>. <b>239</b> (3): <span class="nowrap">455–</span>458. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2FBF02349050">10.1007/BF02349050</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:97425651">97425651</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Radioanalytical+and+Nuclear+Chemistry&rft.atitle=Thermal+neutron+cross+section+and+resonance+integral+of+the+reaction+of135Cs%28n%2C%CE%B3%29136Cs%3A+Fundamental+data+for+the+transmutation+of+nuclear+waste&rft.volume=239&rft.issue=3&rft.pages=%3Cspan+class%3D%22nowrap%22%3E455-%3C%2Fspan%3E458&rft.date=1999&rft_id=info%3Adoi%2F10.1007%2FBF02349050&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A97425651%23id-name%3DS2CID&rft.aulast=Hatsukawa&rft.aufirst=Y.&rft.au=Shinohara%2C+N&rft.au=Hata%2C+K.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-Ohki-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-Ohki_29-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFOhkiTakaki2002" class="citation journal cs1">Ohki, Shigeo; Takaki, Naoyuki (2002). <a rel="nofollow" class="external text" href="http://www.nea.fr/html/pt/docs/iem/jeju02/session6/SessionVI-08.pdf">"Transmutation of Cesium-135 With Fast Reactors"</a> <span class="cs1-format">(PDF)</span>. <i>Proceedings of the Seventh Information Exchange Meeting on Actinide and Fission Product Partitioning & Transmutation, Cheju, Korea</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Proceedings+of+the+Seventh+Information+Exchange+Meeting+on+Actinide+and+Fission+Product+Partitioning+%26+Transmutation%2C+Cheju%2C+Korea&rft.atitle=Transmutation+of+Cesium-135+With+Fast+Reactors&rft.date=2002&rft.aulast=Ohki&rft.aufirst=Shigeo&rft.au=Takaki%2C+Naoyuki&rft_id=http%3A%2F%2Fwww.nea.fr%2Fhtml%2Fpt%2Fdocs%2Fiem%2Fjeju02%2Fsession6%2FSessionVI-08.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www-nds.iaea.org/ngatlas2/">"NGAtlas/ZV"</a>. <i>www-nds.iaea.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2025-02-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www-nds.iaea.org&rft.atitle=NGAtlas%2FZV&rft_id=https%3A%2F%2Fwww-nds.iaea.org%2Fngatlas2%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> <li id="cite_note-137Cs-Normile-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-137Cs-Normile_31-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFDennis2013" class="citation journal cs1">Dennis (1 March 2013). "Cooling a Hot Zone". <i>Science</i>. <b>339</b> (6123): <span class="nowrap">1028–</span>1029. <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.339.6123.1028">10.1126/science.339.6123.1028</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/23449572">23449572</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=Cooling+a+Hot+Zone&rft.volume=339&rft.issue=6123&rft.pages=%3Cspan+class%3D%22nowrap%22%3E1028-%3C%2Fspan%3E1029&rft.date=2013-03-01&rft_id=info%3Adoi%2F10.1126%2Fscience.339.6123.1028&rft_id=info%3Apmid%2F23449572&rft.au=Dennis&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></span> </li> </ol></div></div> <ul><li>Isotope masses from: <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFAudiBersillonBlachotWapstra2003" class="citation cs2">Audi, Georges; Bersillon, Olivier; Blachot, Jean; <a href="/wiki/Aaldert_Wapstra" title="Aaldert Wapstra">Wapstra, Aaldert Hendrik</a> (2003), <a rel="nofollow" class="external text" href="https://hal.archives-ouvertes.fr/in2p3-00020241/document">"The N<small>UBASE</small> evaluation of nuclear and decay properties"</a>, <i>Nuclear Physics A</i>, <b>729</b>: <span class="nowrap">3–</span>128, <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/2003NuPhA.729....3A">2003NuPhA.729....3A</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%2Fj.nuclphysa.2003.11.001">10.1016/j.nuclphysa.2003.11.001</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nuclear+Physics+A&rft.atitle=The+N%3Csmall%3EUBASE%3C%2Fsmall%3E+evaluation+of+nuclear+and+decay+properties&rft.volume=729&rft.pages=%3Cspan+class%3D%22nowrap%22%3E3-%3C%2Fspan%3E128&rft.date=2003&rft_id=info%3Adoi%2F10.1016%2Fj.nuclphysa.2003.11.001&rft_id=info%3Abibcode%2F2003NuPhA.729....3A&rft.aulast=Audi&rft.aufirst=Georges&rft.au=Bersillon%2C+Olivier&rft.au=Blachot%2C+Jean&rft.au=Wapstra%2C+Aaldert+Hendrik&rft_id=https%3A%2F%2Fhal.archives-ouvertes.fr%2Fin2p3-00020241%2Fdocument&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></li></ul></li> <li>Half-life, spin, and isomer data selected from the following sources. <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFAudiBersillonBlachotWapstra2003" class="citation cs2">Audi, Georges; Bersillon, Olivier; Blachot, Jean; <a href="/wiki/Aaldert_Wapstra" title="Aaldert Wapstra">Wapstra, Aaldert Hendrik</a> (2003), <a rel="nofollow" class="external text" href="https://hal.archives-ouvertes.fr/in2p3-00020241/document">"The N<small>UBASE</small> evaluation of nuclear and decay properties"</a>, <i>Nuclear Physics A</i>, <b>729</b>: <span class="nowrap">3–</span>128, <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/2003NuPhA.729....3A">2003NuPhA.729....3A</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%2Fj.nuclphysa.2003.11.001">10.1016/j.nuclphysa.2003.11.001</a></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nuclear+Physics+A&rft.atitle=The+N%3Csmall%3EUBASE%3C%2Fsmall%3E+evaluation+of+nuclear+and+decay+properties&rft.volume=729&rft.pages=%3Cspan+class%3D%22nowrap%22%3E3-%3C%2Fspan%3E128&rft.date=2003&rft_id=info%3Adoi%2F10.1016%2Fj.nuclphysa.2003.11.001&rft_id=info%3Abibcode%2F2003NuPhA.729....3A&rft.aulast=Audi&rft.aufirst=Georges&rft.au=Bersillon%2C+Olivier&rft.au=Blachot%2C+Jean&rft.au=Wapstra%2C+Aaldert+Hendrik&rft_id=https%3A%2F%2Fhal.archives-ouvertes.fr%2Fin2p3-00020241%2Fdocument&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFNational_Nuclear_Data_Center" class="citation web cs1"><a href="/wiki/National_Nuclear_Data_Center" title="National Nuclear Data Center">National Nuclear Data Center</a>. <a rel="nofollow" class="external text" href="http://www.nndc.bnl.gov/nudat2/">"NuDat 2.x database"</a>. <a href="/wiki/Brookhaven_National_Laboratory" title="Brookhaven National Laboratory">Brookhaven National Laboratory</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=NuDat+2.x+database&rft.pub=Brookhaven+National+Laboratory&rft.au=National+Nuclear+Data+Center&rft_id=http%3A%2F%2Fwww.nndc.bnl.gov%2Fnudat2%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFHolden2004" class="citation book cs1">Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). <i><a href="/wiki/CRC_Handbook_of_Chemistry_and_Physics" title="CRC Handbook of Chemistry and Physics">CRC Handbook of Chemistry and Physics</a></i> (85th ed.). <a href="/wiki/Boca_Raton,_Florida" title="Boca Raton, Florida">Boca Raton, Florida</a>: <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=11.+Table+of+the+Isotopes&rft.btitle=CRC+Handbook+of+Chemistry+and+Physics&rft.place=Boca+Raton%2C+Florida&rft.edition=85th&rft.pub=CRC+Press&rft.date=2004&rft.isbn=978-0-8493-0485-9&rft.aulast=Holden&rft.aufirst=Norman+E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AIsotopes+of+caesium" class="Z3988"></span></li></ul></li></ul> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Isotopes_of_the_chemical_elements285" style="padding:3px"><table class="nowraplinks mw-collapsible expanded 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:Navbox_element_isotopes" title="Template:Navbox element isotopes"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Navbox_element_isotopes" title="Template talk:Navbox element isotopes"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Navbox_element_isotopes" title="Special:EditPage/Template:Navbox element isotopes"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Isotopes_of_the_chemical_elements285" style="font-size:114%;margin:0 4em"><a href="/wiki/Isotope" title="Isotope">Isotopes</a> of the <a href="/wiki/Chemical_element" title="Chemical element">chemical elements</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0;line-height:110%;"><div style="padding:0 0.25em"> <table style="border-spacing:1px;display:block;overflow:auto;width:100%;margin:0 !important"> <tbody><tr style="line-height:125%; vertical-align:top;"> <th style="text-align:right; width:3%;"><a href="/wiki/Group_(periodic_table)" title="Group (periodic table)">Group</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Alkali_metal" title="Alkali metal">1</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Alkaline_earth_metal" title="Alkaline earth metal">2</a> </th> <td style="width:2%">  </td> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Group_3_element" title="Group 3 element">3</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Group_4_element" title="Group 4 element">4</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Group_5_element" title="Group 5 element">5</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Group_6_element" title="Group 6 element">6</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Group_7_element" title="Group 7 element">7</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Group_8_element" title="Group 8 element">8</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Group_9_element" title="Group 9 element">9</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Group_10_element" title="Group 10 element">10</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Group_11_element" title="Group 11 element">11</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Group_12_element" title="Group 12 element">12</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Boron_group" title="Boron group">13</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Carbon_group" title="Carbon group">14</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Pnictogen" title="Pnictogen">15</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Chalcogen" title="Chalcogen">16</a> </th> <th style="background:#e8e8e8;color:inherit; width:5%"><a href="/wiki/Halogen" title="Halogen">17</a> </th> <th style="background:#f0f0f0;color:inherit; width:5%"><a href="/wiki/Noble_gas" title="Noble gas">18</a> </th></tr> <tr style="font-size:85%; line-height:125%; vertical-align:top;"> <th style="text-align:left; vertical-align:bottom;"><a href="/wiki/Period_(periodic_table)" title="Period (periodic table)">Period</a> </th> <td style="background:#e8e8e8;color:black;">Hydrogen and<br />alkali metals </td> <td style="background:#f0f0f0;color:black;">Alkaline<br />earth metals </td> <td> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;"> </td> <td style="background:#f0f0f0;color:black;"> </td> <td style="background:#e8e8e8;color:black;">Pnictogens </td> <td style="background:#f0f0f0;color:black;">Chalcogens </td> <td style="background:#e8e8e8;color:black;">Halogens </td> <td style="background:#f0f0f0;color:black;">Noble gases </td></tr> <tr> <th style=""><span title="Period ①" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_1_element" title="Period 1 element">①</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_hydrogen" title="Isotopes of hydrogen">Isotopes</a>  <a href="/wiki/Isotopes_of_hydrogen#List_of_isotopes" title="Isotopes of hydrogen">§ List</a></div><div style="display:block"><b><a href="/wiki/Hydrogen" title="Hydrogen">H</a></b></div>1 </td> <td colspan="17"> </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_helium" title="Isotopes of helium">Isotopes</a>  <a href="/wiki/Isotopes_of_helium#List_of_isotopes" title="Isotopes of helium">§ List</a></div><div style="display:block"><b><a href="/wiki/Helium" title="Helium">He</a></b></div>2 </td></tr> <tr> <th style=""><span title="Period ②" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_2_element" title="Period 2 element">②</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_lithium" title="Isotopes of lithium">Isotopes</a>  <a href="/wiki/Isotopes_of_lithium#List_of_isotopes" title="Isotopes of lithium">§ List</a></div><div style="display:block"><b><a href="/wiki/Lithium" title="Lithium">Li</a></b></div>3 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_beryllium" title="Isotopes of beryllium">Isotopes</a>  <a href="/wiki/Isotopes_of_beryllium#List_of_isotopes" title="Isotopes of beryllium">§ List</a></div><div style="display:block"><b><a href="/wiki/Beryllium" title="Beryllium">Be</a></b></div>4 </td> <td colspan="11"> </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_boron" title="Isotopes of boron">Isotopes</a>  <a href="/wiki/Isotopes_of_boron#List_of_isotopes" title="Isotopes of boron">§ List</a></div><div style="display:block"><b><a href="/wiki/Boron" title="Boron">B</a></b></div>5 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_carbon" title="Isotopes of carbon">Isotopes</a>  <a href="/wiki/Isotopes_of_carbon#List_of_isotopes" title="Isotopes of carbon">§ List</a></div><div style="display:block"><b><a href="/wiki/Carbon" title="Carbon">C</a></b></div>6 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_nitrogen" title="Isotopes of nitrogen">Isotopes</a>  <a href="/wiki/Isotopes_of_nitrogen#List_of_isotopes" title="Isotopes of nitrogen">§ List</a></div><div style="display:block"><b><a href="/wiki/Nitrogen" title="Nitrogen">N</a></b></div>7 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_oxygen" title="Isotopes of oxygen">Isotopes</a>  <a href="/wiki/Isotopes_of_oxygen#List_of_isotopes" title="Isotopes of oxygen">§ List</a></div><div style="display:block"><b><a href="/wiki/Oxygen" title="Oxygen">O</a></b></div>8 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_fluorine" title="Isotopes of fluorine">Isotopes</a>  <a href="/wiki/Isotopes_of_fluorine#List_of_isotopes" title="Isotopes of fluorine">§ List</a></div><div style="display:block"><b><a href="/wiki/Fluorine" title="Fluorine">F</a></b></div>9 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_neon" title="Isotopes of neon">Isotopes</a>  <a href="/wiki/Isotopes_of_neon#List_of_isotopes" title="Isotopes of neon">§ List</a></div><div style="display:block"><b><a href="/wiki/Neon" title="Neon">Ne</a></b></div>10 </td></tr> <tr> <th style=""><span title="Period ③" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_3_element" title="Period 3 element">③</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_sodium" title="Isotopes of sodium">Isotopes</a>  <a href="/wiki/Isotopes_of_sodium#List_of_isotopes" title="Isotopes of sodium">§ List</a></div><div style="display:block"><b><a href="/wiki/Sodium" title="Sodium">Na</a></b></div>11 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_magnesium" title="Isotopes of magnesium">Isotopes</a>  <a href="/wiki/Isotopes_of_magnesium#List_of_isotopes" title="Isotopes of magnesium">§ List</a></div><div style="display:block"><b><a href="/wiki/Magnesium" title="Magnesium">Mg</a></b></div>12 </td> <td colspan="11"> </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_aluminium" title="Isotopes of aluminium">Isotopes</a>  <a href="/wiki/Isotopes_of_aluminium#List_of_isotopes" title="Isotopes of aluminium">§ List</a></div><div style="display:block"><b><a href="/wiki/Aluminium" title="Aluminium">Al</a></b></div>13 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_silicon" title="Isotopes of silicon">Isotopes</a>  <a href="/wiki/Isotopes_of_silicon#List_of_isotopes" title="Isotopes of silicon">§ List</a></div><div style="display:block"><b><a href="/wiki/Silicon" title="Silicon">Si</a></b></div>14 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_phosphorus" title="Isotopes of phosphorus">Isotopes</a>  <a href="/wiki/Isotopes_of_phosphorus#List_of_isotopes" title="Isotopes of phosphorus">§ List</a></div><div style="display:block"><b><a href="/wiki/Phosphorus" title="Phosphorus">P</a></b></div>15 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_sulfur" title="Isotopes of sulfur">Isotopes</a>  <a href="/wiki/Isotopes_of_sulfur#List_of_isotopes" title="Isotopes of sulfur">§ List</a></div><div style="display:block"><b><a href="/wiki/Sulfur" title="Sulfur">S</a></b></div>16 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_chlorine" title="Isotopes of chlorine">Isotopes</a>  <a href="/wiki/Isotopes_of_chlorine#List_of_isotopes" title="Isotopes of chlorine">§ List</a></div><div style="display:block"><b><a href="/wiki/Chlorine" title="Chlorine">Cl</a></b></div>17 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_argon" title="Isotopes of argon">Isotopes</a>  <a href="/wiki/Isotopes_of_argon#List_of_isotopes" title="Isotopes of argon">§ List</a></div><div style="display:block"><b><a href="/wiki/Argon" title="Argon">Ar</a></b></div>18 </td></tr> <tr> <th style=""><span title="Period ④" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_4_element" title="Period 4 element">④</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_potassium" title="Isotopes of potassium">Isotopes</a>  <a href="/wiki/Isotopes_of_potassium#List_of_isotopes" title="Isotopes of potassium">§ List</a></div><div style="display:block"><b><a href="/wiki/Potassium" title="Potassium">K</a></b></div>19 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_calcium" title="Isotopes of calcium">Isotopes</a>  <a href="/wiki/Isotopes_of_calcium#List_of_isotopes" title="Isotopes of calcium">§ List</a></div><div style="display:block"><b><a href="/wiki/Calcium" title="Calcium">Ca</a></b></div>20 </td> <td> </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_scandium" title="Isotopes of scandium">Isotopes</a>  <a href="/wiki/Isotopes_of_scandium#List_of_isotopes" title="Isotopes of scandium">§ List</a></div><div style="display:block"><b><a href="/wiki/Scandium" title="Scandium">Sc</a></b></div>21 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_titanium" title="Isotopes of titanium">Isotopes</a>  <a href="/wiki/Isotopes_of_titanium#List_of_isotopes" title="Isotopes of titanium">§ List</a></div><div style="display:block"><b><a href="/wiki/Titanium" title="Titanium">Ti</a></b></div>22 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_vanadium" title="Isotopes of vanadium">Isotopes</a>  <a href="/wiki/Isotopes_of_vanadium#List_of_isotopes" title="Isotopes of vanadium">§ List</a></div><div style="display:block"><b><a href="/wiki/Vanadium" title="Vanadium">V</a></b></div>23 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_chromium" title="Isotopes of chromium">Isotopes</a>  <a href="/wiki/Isotopes_of_chromium#List_of_isotopes" title="Isotopes of chromium">§ List</a></div><div style="display:block"><b><a href="/wiki/Chromium" title="Chromium">Cr</a></b></div>24 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_manganese" title="Isotopes of manganese">Isotopes</a>  <a href="/wiki/Isotopes_of_manganese#List_of_isotopes" title="Isotopes of manganese">§ List</a></div><div style="display:block"><b><a href="/wiki/Manganese" title="Manganese">Mn</a></b></div>25 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_iron" title="Isotopes of iron">Isotopes</a>  <a href="/wiki/Isotopes_of_iron#List_of_isotopes" title="Isotopes of iron">§ List</a></div><div style="display:block"><b><a href="/wiki/Iron" title="Iron">Fe</a></b></div>26 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_cobalt" title="Isotopes of cobalt">Isotopes</a>  <a href="/wiki/Isotopes_of_cobalt#List_of_isotopes" title="Isotopes of cobalt">§ List</a></div><div style="display:block"><b><a href="/wiki/Cobalt" title="Cobalt">Co</a></b></div>27 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_nickel" title="Isotopes of nickel">Isotopes</a>  <a href="/wiki/Isotopes_of_nickel#List_of_isotopes" title="Isotopes of nickel">§ List</a></div><div style="display:block"><b><a href="/wiki/Nickel" title="Nickel">Ni</a></b></div>28 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_copper" title="Isotopes of copper">Isotopes</a>  <a href="/wiki/Isotopes_of_copper#List_of_isotopes" title="Isotopes of copper">§ List</a></div><div style="display:block"><b><a href="/wiki/Copper" title="Copper">Cu</a></b></div>29 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_zinc" title="Isotopes of zinc">Isotopes</a>  <a href="/wiki/Isotopes_of_zinc#List_of_isotopes" title="Isotopes of zinc">§ List</a></div><div style="display:block"><b><a href="/wiki/Zinc" title="Zinc">Zn</a></b></div>30 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_gallium" title="Isotopes of gallium">Isotopes</a>  <a href="/wiki/Isotopes_of_gallium#List_of_isotopes" title="Isotopes of gallium">§ List</a></div><div style="display:block"><b><a href="/wiki/Gallium" title="Gallium">Ga</a></b></div>31 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_germanium" title="Isotopes of germanium">Isotopes</a>  <a href="/wiki/Isotopes_of_germanium#List_of_isotopes" title="Isotopes of germanium">§ List</a></div><div style="display:block"><b><a href="/wiki/Germanium" title="Germanium">Ge</a></b></div>32 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_arsenic" title="Isotopes of arsenic">Isotopes</a>  <a href="/wiki/Isotopes_of_arsenic#List_of_isotopes" title="Isotopes of arsenic">§ List</a></div><div style="display:block"><b><a href="/wiki/Arsenic" title="Arsenic">As</a></b></div>33 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_selenium" title="Isotopes of selenium">Isotopes</a>  <a href="/wiki/Isotopes_of_selenium#List_of_isotopes" title="Isotopes of selenium">§ List</a></div><div style="display:block"><b><a href="/wiki/Selenium" title="Selenium">Se</a></b></div>34 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_bromine" title="Isotopes of bromine">Isotopes</a>  <a href="/wiki/Isotopes_of_bromine#List_of_isotopes" title="Isotopes of bromine">§ List</a></div><div style="display:block"><b><a href="/wiki/Bromine" title="Bromine">Br</a></b></div>35 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_krypton" title="Isotopes of krypton">Isotopes</a>  <a href="/wiki/Isotopes_of_krypton#List_of_isotopes" title="Isotopes of krypton">§ List</a></div><div style="display:block"><b><a href="/wiki/Krypton" title="Krypton">Kr</a></b></div>36 </td></tr> <tr> <th style=""><span title="Period ⑤" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_5_element" title="Period 5 element">⑤</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_rubidium" title="Isotopes of rubidium">Isotopes</a>  <a href="/wiki/Isotopes_of_rubidium#List_of_isotopes" title="Isotopes of rubidium">§ List</a></div><div style="display:block"><b><a href="/wiki/Rubidium" title="Rubidium">Rb</a></b></div>37 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_strontium" title="Isotopes of strontium">Isotopes</a>  <a href="/wiki/Isotopes_of_strontium#List_of_isotopes" title="Isotopes of strontium">§ List</a></div><div style="display:block"><b><a href="/wiki/Strontium" title="Strontium">Sr</a></b></div>38 </td> <td> </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_yttrium" title="Isotopes of yttrium">Isotopes</a>  <a href="/wiki/Isotopes_of_yttrium#List_of_isotopes" title="Isotopes of yttrium">§ List</a></div><div style="display:block"><b><a href="/wiki/Yttrium" title="Yttrium">Y</a></b></div>39 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_zirconium" title="Isotopes of zirconium">Isotopes</a>  <a href="/wiki/Isotopes_of_zirconium#List_of_isotopes" title="Isotopes of zirconium">§ List</a></div><div style="display:block"><b><a href="/wiki/Zirconium" title="Zirconium">Zr</a></b></div>40 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_niobium" title="Isotopes of niobium">Isotopes</a>  <a href="/wiki/Isotopes_of_niobium#List_of_isotopes" title="Isotopes of niobium">§ List</a></div><div style="display:block"><b><a href="/wiki/Niobium" title="Niobium">Nb</a></b></div>41 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_molybdenum" title="Isotopes of molybdenum">Isotopes</a>  <a href="/wiki/Isotopes_of_molybdenum#List_of_isotopes" title="Isotopes of molybdenum">§ List</a></div><div style="display:block"><b><a href="/wiki/Molybdenum" title="Molybdenum">Mo</a></b></div>42 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_technetium" title="Isotopes of technetium">Isotopes</a>  <a href="/wiki/Isotopes_of_technetium#List_of_isotopes" title="Isotopes of technetium">§ List</a></div><div style="display:block"><b><a href="/wiki/Technetium" title="Technetium">Tc</a></b></div>43 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_ruthenium" title="Isotopes of ruthenium">Isotopes</a>  <a href="/wiki/Isotopes_of_ruthenium#List_of_isotopes" title="Isotopes of ruthenium">§ List</a></div><div style="display:block"><b><a href="/wiki/Ruthenium" title="Ruthenium">Ru</a></b></div>44 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_rhodium" title="Isotopes of rhodium">Isotopes</a>  <a href="/wiki/Isotopes_of_rhodium#List_of_isotopes" title="Isotopes of rhodium">§ List</a></div><div style="display:block"><b><a href="/wiki/Rhodium" title="Rhodium">Rh</a></b></div>45 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_palladium" title="Isotopes of palladium">Isotopes</a>  <a href="/wiki/Isotopes_of_palladium#List_of_isotopes" title="Isotopes of palladium">§ List</a></div><div style="display:block"><b><a href="/wiki/Palladium" title="Palladium">Pd</a></b></div>46 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_silver" title="Isotopes of silver">Isotopes</a>  <a href="/wiki/Isotopes_of_silver#List_of_isotopes" title="Isotopes of silver">§ List</a></div><div style="display:block"><b><a href="/wiki/Silver" title="Silver">Ag</a></b></div>47 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_cadmium" title="Isotopes of cadmium">Isotopes</a>  <a href="/wiki/Isotopes_of_cadmium#List_of_isotopes" title="Isotopes of cadmium">§ List</a></div><div style="display:block"><b><a href="/wiki/Cadmium" title="Cadmium">Cd</a></b></div>48 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_indium" title="Isotopes of indium">Isotopes</a>  <a href="/wiki/Isotopes_of_indium#List_of_isotopes" title="Isotopes of indium">§ List</a></div><div style="display:block"><b><a href="/wiki/Indium" title="Indium">In</a></b></div>49 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_tin" title="Isotopes of tin">Isotopes</a>  <a href="/wiki/Isotopes_of_tin#List_of_isotopes" title="Isotopes of tin">§ List</a></div><div style="display:block"><b><a href="/wiki/Tin" title="Tin">Sn</a></b></div>50 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_antimony" title="Isotopes of antimony">Isotopes</a>  <a href="/wiki/Isotopes_of_antimony#List_of_isotopes" title="Isotopes of antimony">§ List</a></div><div style="display:block"><b><a href="/wiki/Antimony" title="Antimony">Sb</a></b></div>51 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_tellurium" title="Isotopes of tellurium">Isotopes</a>  <a href="/wiki/Isotopes_of_tellurium#List_of_isotopes" title="Isotopes of tellurium">§ List</a></div><div style="display:block"><b><a href="/wiki/Tellurium" title="Tellurium">Te</a></b></div>52 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_iodine" title="Isotopes of iodine">Isotopes</a>  <a href="/wiki/Isotopes_of_iodine#List_of_isotopes" title="Isotopes of iodine">§ List</a></div><div style="display:block"><b><a href="/wiki/Iodine" title="Iodine">I</a></b></div>53 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_xenon" title="Isotopes of xenon">Isotopes</a>  <a href="/wiki/Isotopes_of_xenon#List_of_isotopes" title="Isotopes of xenon">§ List</a></div><div style="display:block"><b><a href="/wiki/Xenon" title="Xenon">Xe</a></b></div>54 </td></tr> <tr> <th style=""><span title="Period ⑥" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_6_element" title="Period 6 element">⑥</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a class="mw-selflink selflink">Isotopes</a>  <a class="mw-selflink-fragment" href="#List_of_isotopes">§ List</a></div><div style="display:block"><b><a href="/wiki/Caesium" title="Caesium">Cs</a></b></div>55 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_barium" title="Isotopes of barium">Isotopes</a>  <a href="/wiki/Isotopes_of_barium#List_of_isotopes" title="Isotopes of barium">§ List</a></div><div style="display:block"><b><a href="/wiki/Barium" title="Barium">Ba</a></b></div>56 </td> <td style="text-align:center; vertical-align:middle; background:#9bff99;color:inherit;"><span class="skin-invert-image" typeof="mw:File"><span><img alt="1 asterisk" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Asterisks_one.svg/20px-Asterisks_one.svg.png" decoding="async" width="16" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Asterisks_one.svg/40px-Asterisks_one.svg.png 1.5x" data-file-width="106" data-file-height="98" /></span></span> </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_lutetium" title="Isotopes of lutetium">Isotopes</a>  <a href="/wiki/Isotopes_of_lutetium#List_of_isotopes" title="Isotopes of lutetium">§ List</a></div><div style="display:block"><b><a href="/wiki/Lutetium" title="Lutetium">Lu</a></b></div>71 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_hafnium" title="Isotopes of hafnium">Isotopes</a>  <a href="/wiki/Isotopes_of_hafnium#List_of_isotopes" title="Isotopes of hafnium">§ List</a></div><div style="display:block"><b><a href="/wiki/Hafnium" title="Hafnium">Hf</a></b></div>72 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_tantalum" title="Isotopes of tantalum">Isotopes</a>  <a href="/wiki/Isotopes_of_tantalum#List_of_isotopes" title="Isotopes of tantalum">§ List</a></div><div style="display:block"><b><a href="/wiki/Tantalum" title="Tantalum">Ta</a></b></div>73 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_tungsten" title="Isotopes of tungsten">Isotopes</a>  <a href="/wiki/Isotopes_of_tungsten#List_of_isotopes" title="Isotopes of tungsten">§ List</a></div><div style="display:block"><b><a href="/wiki/Tungsten" title="Tungsten">W</a></b></div>74 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_rhenium" title="Isotopes of rhenium">Isotopes</a>  <a href="/wiki/Isotopes_of_rhenium#List_of_isotopes" title="Isotopes of rhenium">§ List</a></div><div style="display:block"><b><a href="/wiki/Rhenium" title="Rhenium">Re</a></b></div>75 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_osmium" title="Isotopes of osmium">Isotopes</a>  <a href="/wiki/Isotopes_of_osmium#List_of_isotopes" title="Isotopes of osmium">§ List</a></div><div style="display:block"><b><a href="/wiki/Osmium" title="Osmium">Os</a></b></div>76 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_iridium" title="Isotopes of iridium">Isotopes</a>  <a href="/wiki/Isotopes_of_iridium#List_of_isotopes" title="Isotopes of iridium">§ List</a></div><div style="display:block"><b><a href="/wiki/Iridium" title="Iridium">Ir</a></b></div>77 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_platinum" title="Isotopes of platinum">Isotopes</a>  <a href="/wiki/Isotopes_of_platinum#List_of_isotopes" title="Isotopes of platinum">§ List</a></div><div style="display:block"><b><a href="/wiki/Platinum" title="Platinum">Pt</a></b></div>78 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_gold" title="Isotopes of gold">Isotopes</a>  <a href="/wiki/Isotopes_of_gold#List_of_isotopes" title="Isotopes of gold">§ List</a></div><div style="display:block"><b><a href="/wiki/Gold" title="Gold">Au</a></b></div>79 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_mercury" title="Isotopes of mercury">Isotopes</a>  <a href="/wiki/Isotopes_of_mercury#List_of_isotopes" title="Isotopes of mercury">§ List</a></div><div style="display:block"><b><a href="/wiki/Mercury_(element)" title="Mercury (element)">Hg</a></b></div>80 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_thallium" title="Isotopes of thallium">Isotopes</a>  <a href="/wiki/Isotopes_of_thallium#List_of_isotopes" title="Isotopes of thallium">§ List</a></div><div style="display:block"><b><a href="/wiki/Thallium" title="Thallium">Tl</a></b></div>81 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_lead" title="Isotopes of lead">Isotopes</a>  <a href="/wiki/Isotopes_of_lead#List_of_isotopes" title="Isotopes of lead">§ List</a></div><div style="display:block"><b><a href="/wiki/Lead" title="Lead">Pb</a></b></div>82 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_bismuth" title="Isotopes of bismuth">Isotopes</a>  <a href="/wiki/Isotopes_of_bismuth#List_of_isotopes" title="Isotopes of bismuth">§ List</a></div><div style="display:block"><b><a href="/wiki/Bismuth" title="Bismuth">Bi</a></b></div>83 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_polonium" title="Isotopes of polonium">Isotopes</a>  <a href="/wiki/Isotopes_of_polonium#List_of_isotopes" title="Isotopes of polonium">§ List</a></div><div style="display:block"><b><a href="/wiki/Polonium" title="Polonium">Po</a></b></div>84 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_astatine" title="Isotopes of astatine">Isotopes</a>  <a href="/wiki/Isotopes_of_astatine#List_of_isotopes" title="Isotopes of astatine">§ List</a></div><div style="display:block"><b><a href="/wiki/Astatine" title="Astatine">At</a></b></div>85 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_radon" title="Isotopes of radon">Isotopes</a>  <a href="/wiki/Isotopes_of_radon#List_of_isotopes" title="Isotopes of radon">§ List</a></div><div style="display:block"><b><a href="/wiki/Radon" title="Radon">Rn</a></b></div>86 </td></tr> <tr> <th style=""><span title="Period ⑦" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_7_element" title="Period 7 element">⑦</a></span> </th> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_francium" title="Isotopes of francium">Isotopes</a>  <a href="/wiki/Isotopes_of_francium#List_of_isotopes" title="Isotopes of francium">§ List</a></div><div style="display:block"><b><a href="/wiki/Francium" title="Francium">Fr</a></b></div>87 </td> <td style="padding-left:0.1em; background:#ff9999;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_radium" title="Isotopes of radium">Isotopes</a>  <a href="/wiki/Isotopes_of_radium#List_of_isotopes" title="Isotopes of radium">§ List</a></div><div style="display:block"><b><a href="/wiki/Radium" title="Radium">Ra</a></b></div>88 </td> <td style="text-align:center; vertical-align:middle; background:#9bff99;color:inherit;"><span class="skin-invert-image" typeof="mw:File"><span><img alt="1 asterisk" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/16px-Asterisks_2_%28vertical%29.svg.png" decoding="async" width="16" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/24px-Asterisks_2_%28vertical%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/32px-Asterisks_2_%28vertical%29.svg.png 2x" data-file-width="106" data-file-height="98" /></span></span> </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_lawrencium" title="Isotopes of lawrencium">Isotopes</a>  <a href="/wiki/Isotopes_of_lawrencium#List_of_isotopes" title="Isotopes of lawrencium">§ List</a></div><div style="display:block"><b><a href="/wiki/Lawrencium" title="Lawrencium">Lr</a></b></div>103 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_rutherfordium" title="Isotopes of rutherfordium">Isotopes</a>  <a href="/wiki/Isotopes_of_rutherfordium#List_of_isotopes" title="Isotopes of rutherfordium">§ List</a></div><div style="display:block"><b><a href="/wiki/Rutherfordium" title="Rutherfordium">Rf</a></b></div>104 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_dubnium" title="Isotopes of dubnium">Isotopes</a>  <a href="/wiki/Isotopes_of_dubnium#List_of_isotopes" title="Isotopes of dubnium">§ List</a></div><div style="display:block"><b><a href="/wiki/Dubnium" title="Dubnium">Db</a></b></div>105 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_seaborgium" title="Isotopes of seaborgium">Isotopes</a>  <a href="/wiki/Isotopes_of_seaborgium#List_of_isotopes" title="Isotopes of seaborgium">§ List</a></div><div style="display:block"><b><a href="/wiki/Seaborgium" title="Seaborgium">Sg</a></b></div>106 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_bohrium" title="Isotopes of bohrium">Isotopes</a>  <a href="/wiki/Isotopes_of_bohrium#List_of_isotopes" title="Isotopes of bohrium">§ List</a></div><div style="display:block"><b><a href="/wiki/Bohrium" title="Bohrium">Bh</a></b></div>107 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_hassium" title="Isotopes of hassium">Isotopes</a>  <a href="/wiki/Isotopes_of_hassium#List_of_isotopes" title="Isotopes of hassium">§ List</a></div><div style="display:block"><b><a href="/wiki/Hassium" title="Hassium">Hs</a></b></div>108 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_meitnerium" title="Isotopes of meitnerium">Isotopes</a>  <a href="/wiki/Isotopes_of_meitnerium#List_of_isotopes" title="Isotopes of meitnerium">§ List</a></div><div style="display:block"><b><a href="/wiki/Meitnerium" title="Meitnerium">Mt</a></b></div>109 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_darmstadtium" title="Isotopes of darmstadtium">Isotopes</a>  <a href="/wiki/Isotopes_of_darmstadtium#List_of_isotopes" title="Isotopes of darmstadtium">§ List</a></div><div style="display:block"><b><a href="/wiki/Darmstadtium" title="Darmstadtium">Ds</a></b></div>110 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_roentgenium" title="Isotopes of roentgenium">Isotopes</a>  <a href="/wiki/Isotopes_of_roentgenium#List_of_isotopes" title="Isotopes of roentgenium">§ List</a></div><div style="display:block"><b><a href="/wiki/Roentgenium" title="Roentgenium">Rg</a></b></div>111 </td> <td style="padding-left:0.1em; background:#99ccff;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_copernicium" title="Isotopes of copernicium">Isotopes</a>  <a href="/wiki/Isotopes_of_copernicium#List_of_isotopes" title="Isotopes of copernicium">§ List</a></div><div style="display:block"><b><a href="/wiki/Copernicium" title="Copernicium">Cn</a></b></div>112 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_nihonium" title="Isotopes of nihonium">Isotopes</a>  <a href="/wiki/Isotopes_of_nihonium#List_of_isotopes" title="Isotopes of nihonium">§ List</a></div><div style="display:block"><b><a href="/wiki/Nihonium" title="Nihonium">Nh</a></b></div>113 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_flerovium" title="Isotopes of flerovium">Isotopes</a>  <a href="/wiki/Isotopes_of_flerovium#List_of_isotopes" title="Isotopes of flerovium">§ List</a></div><div style="display:block"><b><a href="/wiki/Flerovium" title="Flerovium">Fl</a></b></div>114 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_moscovium" title="Isotopes of moscovium">Isotopes</a>  <a href="/wiki/Isotopes_of_moscovium#List_of_isotopes" title="Isotopes of moscovium">§ List</a></div><div style="display:block"><b><a href="/wiki/Moscovium" title="Moscovium">Mc</a></b></div>115 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_livermorium" title="Isotopes of livermorium">Isotopes</a>  <a href="/wiki/Isotopes_of_livermorium#List_of_isotopes" title="Isotopes of livermorium">§ List</a></div><div style="display:block"><b><a href="/wiki/Livermorium" title="Livermorium">Lv</a></b></div>116 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_tennessine" title="Isotopes of tennessine">Isotopes</a>  <a href="/wiki/Isotopes_of_tennessine#List_of_isotopes" title="Isotopes of tennessine">§ List</a></div><div style="display:block"><b><a href="/wiki/Tennessine" title="Tennessine">Ts</a></b></div>117 </td> <td style="padding-left:0.1em; background:#fdff8c;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_oganesson" title="Isotopes of oganesson">Isotopes</a>  <a href="/wiki/Isotopes_of_oganesson#List_of_isotopes" title="Isotopes of oganesson">§ List</a></div><div style="display:block"><b><a href="/wiki/Oganesson" title="Oganesson">Og</a></b></div>118 </td></tr> <tr> <th style=""><span title="Period ⑧" class="nounderlines" style="font-size:150%;"><a href="/wiki/Period_8_element" class="mw-redirect" title="Period 8 element">⑧</a></span> </th> <td style="padding-left:0.1em; background:#eee;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_ununennium" title="Isotopes of ununennium">Isotopes</a>  <a href="/wiki/Isotopes_of_ununennium#List_of_isotopes" title="Isotopes of ununennium">§ List</a></div><div style="display:block"><b><a href="/wiki/Ununennium" title="Ununennium">Uue</a></b></div>119 </td> <td style="padding-left:0.1em; background:#eee;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_unbinilium" title="Isotopes of unbinilium">Isotopes</a>  <a href="/wiki/Isotopes_of_unbinilium#List_of_isotopes" title="Isotopes of unbinilium">§ List</a></div><div style="display:block"><b><a href="/wiki/Unbinilium" title="Unbinilium">Ubn</a></b></div>120 </td></tr> <tr> <td colspan="20" style="height:1.4em;"> </td></tr> <tr> <td> </td> <td> </td> <td> </td> <td style="text-align:center; vertical-align:middle;"><span class="skin-invert-image" typeof="mw:File"><span><img alt="1 asterisk" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Asterisks_one.svg/20px-Asterisks_one.svg.png" decoding="async" width="16" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/49/Asterisks_one.svg/40px-Asterisks_one.svg.png 1.5x" data-file-width="106" data-file-height="98" /></span></span> </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_lanthanum" title="Isotopes of lanthanum">Isotopes</a>  <a href="/wiki/Isotopes_of_lanthanum#List_of_isotopes" title="Isotopes of lanthanum">§ List</a></div><div style="display:block"><b><a href="/wiki/Lanthanum" title="Lanthanum">La</a></b></div>57 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_cerium" title="Isotopes of cerium">Isotopes</a>  <a href="/wiki/Isotopes_of_cerium#List_of_isotopes" title="Isotopes of cerium">§ List</a></div><div style="display:block"><b><a href="/wiki/Cerium" title="Cerium">Ce</a></b></div>58 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_praseodymium" title="Isotopes of praseodymium">Isotopes</a>  <a href="/wiki/Isotopes_of_praseodymium#List_of_isotopes" title="Isotopes of praseodymium">§ List</a></div><div style="display:block"><b><a href="/wiki/Praseodymium" title="Praseodymium">Pr</a></b></div>59 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_neodymium" title="Isotopes of neodymium">Isotopes</a>  <a href="/wiki/Isotopes_of_neodymium#List_of_isotopes" title="Isotopes of neodymium">§ List</a></div><div style="display:block"><b><a href="/wiki/Neodymium" title="Neodymium">Nd</a></b></div>60 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_promethium" title="Isotopes of promethium">Isotopes</a>  <a href="/wiki/Isotopes_of_promethium#List_of_isotopes" title="Isotopes of promethium">§ List</a></div><div style="display:block"><b><a href="/wiki/Promethium" title="Promethium">Pm</a></b></div>61 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_samarium" title="Isotopes of samarium">Isotopes</a>  <a href="/wiki/Isotopes_of_samarium#List_of_isotopes" title="Isotopes of samarium">§ List</a></div><div style="display:block"><b><a href="/wiki/Samarium" title="Samarium">Sm</a></b></div>62 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_europium" title="Isotopes of europium">Isotopes</a>  <a href="/wiki/Isotopes_of_europium#List_of_isotopes" title="Isotopes of europium">§ List</a></div><div style="display:block"><b><a href="/wiki/Europium" title="Europium">Eu</a></b></div>63 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_gadolinium" title="Isotopes of gadolinium">Isotopes</a>  <a href="/wiki/Isotopes_of_gadolinium#List_of_isotopes" title="Isotopes of gadolinium">§ List</a></div><div style="display:block"><b><a href="/wiki/Gadolinium" title="Gadolinium">Gd</a></b></div>64 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_terbium" title="Isotopes of terbium">Isotopes</a>  <a href="/wiki/Isotopes_of_terbium#List_of_isotopes" title="Isotopes of terbium">§ List</a></div><div style="display:block"><b><a href="/wiki/Terbium" title="Terbium">Tb</a></b></div>65 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_dysprosium" title="Isotopes of dysprosium">Isotopes</a>  <a href="/wiki/Isotopes_of_dysprosium#List_of_isotopes" title="Isotopes of dysprosium">§ List</a></div><div style="display:block"><b><a href="/wiki/Dysprosium" title="Dysprosium">Dy</a></b></div>66 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_holmium" title="Isotopes of holmium">Isotopes</a>  <a href="/wiki/Isotopes_of_holmium#List_of_isotopes" title="Isotopes of holmium">§ List</a></div><div style="display:block"><b><a href="/wiki/Holmium" title="Holmium">Ho</a></b></div>67 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_erbium" title="Isotopes of erbium">Isotopes</a>  <a href="/wiki/Isotopes_of_erbium#List_of_isotopes" title="Isotopes of erbium">§ List</a></div><div style="display:block"><b><a href="/wiki/Erbium" title="Erbium">Er</a></b></div>68 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_thulium" title="Isotopes of thulium">Isotopes</a>  <a href="/wiki/Isotopes_of_thulium#List_of_isotopes" title="Isotopes of thulium">§ List</a></div><div style="display:block"><b><a href="/wiki/Thulium" title="Thulium">Tm</a></b></div>69 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_ytterbium" title="Isotopes of ytterbium">Isotopes</a>  <a href="/wiki/Isotopes_of_ytterbium#List_of_isotopes" title="Isotopes of ytterbium">§ List</a></div><div style="display:block"><b><a href="/wiki/Ytterbium" title="Ytterbium">Yb</a></b></div>70 </td> <td>  </td></tr> <tr> <td colspan="3"> </td> <td style="text-align:center; vertical-align:middle;"><span class="skin-invert-image" typeof="mw:File"><span><img alt="1 asterisk" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/16px-Asterisks_2_%28vertical%29.svg.png" decoding="async" width="16" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/24px-Asterisks_2_%28vertical%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Asterisks_2_%28vertical%29.svg/32px-Asterisks_2_%28vertical%29.svg.png 2x" data-file-width="106" data-file-height="98" /></span></span> </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_actinium" title="Isotopes of actinium">Isotopes</a>  <a href="/wiki/Isotopes_of_actinium#List_of_isotopes" title="Isotopes of actinium">§ List</a></div><div style="display:block"><b><a href="/wiki/Actinium" title="Actinium">Ac</a></b></div>89 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_thorium" title="Isotopes of thorium">Isotopes</a>  <a href="/wiki/Isotopes_of_thorium#List_of_isotopes" title="Isotopes of thorium">§ List</a></div><div style="display:block"><b><a href="/wiki/Thorium" title="Thorium">Th</a></b></div>90 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_protactinium" title="Isotopes of protactinium">Isotopes</a>  <a href="/wiki/Isotopes_of_protactinium#List_of_isotopes" title="Isotopes of protactinium">§ List</a></div><div style="display:block"><b><a href="/wiki/Protactinium" title="Protactinium">Pa</a></b></div>91 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_uranium" title="Isotopes of uranium">Isotopes</a>  <a href="/wiki/Isotopes_of_uranium#List_of_isotopes" title="Isotopes of uranium">§ List</a></div><div style="display:block"><b><a href="/wiki/Uranium" title="Uranium">U</a></b></div>92 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_neptunium" title="Isotopes of neptunium">Isotopes</a>  <a href="/wiki/Isotopes_of_neptunium#List_of_isotopes" title="Isotopes of neptunium">§ List</a></div><div style="display:block"><b><a href="/wiki/Neptunium" title="Neptunium">Np</a></b></div>93 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_plutonium" title="Isotopes of plutonium">Isotopes</a>  <a href="/wiki/Isotopes_of_plutonium#List_of_isotopes" title="Isotopes of plutonium">§ List</a></div><div style="display:block"><b><a href="/wiki/Plutonium" title="Plutonium">Pu</a></b></div>94 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_americium" title="Isotopes of americium">Isotopes</a>  <a href="/wiki/Isotopes_of_americium#List_of_isotopes" title="Isotopes of americium">§ List</a></div><div style="display:block"><b><a href="/wiki/Americium" title="Americium">Am</a></b></div>95 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_curium" title="Isotopes of curium">Isotopes</a>  <a href="/wiki/Isotopes_of_curium#List_of_isotopes" title="Isotopes of curium">§ List</a></div><div style="display:block"><b><a href="/wiki/Curium" title="Curium">Cm</a></b></div>96 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_berkelium" title="Isotopes of berkelium">Isotopes</a>  <a href="/wiki/Isotopes_of_berkelium#List_of_isotopes" title="Isotopes of berkelium">§ List</a></div><div style="display:block"><b><a href="/wiki/Berkelium" title="Berkelium">Bk</a></b></div>97 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_californium" title="Isotopes of californium">Isotopes</a>  <a href="/wiki/Isotopes_of_californium#List_of_isotopes" title="Isotopes of californium">§ List</a></div><div style="display:block"><b><a href="/wiki/Californium" title="Californium">Cf</a></b></div>98 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_einsteinium" title="Isotopes of einsteinium">Isotopes</a>  <a href="/wiki/Isotopes_of_einsteinium#List_of_isotopes" title="Isotopes of einsteinium">§ List</a></div><div style="display:block"><b><a href="/wiki/Einsteinium" title="Einsteinium">Es</a></b></div>99 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_fermium" title="Isotopes of fermium">Isotopes</a>  <a href="/wiki/Isotopes_of_fermium#List_of_isotopes" title="Isotopes of fermium">§ List</a></div><div style="display:block"><b><a href="/wiki/Fermium" title="Fermium">Fm</a></b></div>100 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_mendelevium" title="Isotopes of mendelevium">Isotopes</a>  <a href="/wiki/Isotopes_of_mendelevium#List_of_isotopes" title="Isotopes of mendelevium">§ List</a></div><div style="display:block"><b><a href="/wiki/Mendelevium" title="Mendelevium">Md</a></b></div>101 </td> <td style="padding-left:0.1em; background:#9bff99;color:inherit;"><div style="text-align:left"><a href="/wiki/Isotopes_of_nobelium" title="Isotopes of nobelium">Isotopes</a>  <a href="/wiki/Isotopes_of_nobelium#List_of_isotopes" title="Isotopes of nobelium">§ List</a></div><div style="display:block"><b><a href="/wiki/Nobelium" title="Nobelium">No</a></b></div>102 </td></tr></tbody></table> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2" style="background:#f0f0f0;color:inherit;"><div> <ul><li><a href="/wiki/Table_of_nuclides" title="Table of nuclides">Table of nuclides</a></li> <li>Categories: <a href="/wiki/Category:Isotopes" title="Category:Isotopes">Isotopes</a></li> <li><a href="/wiki/Category:Tables_of_nuclides" title="Category:Tables of nuclides">Tables of nuclides</a></li> <li><a href="/wiki/Category:Metastable_isotopes" title="Category:Metastable isotopes">Metastable isotopes</a></li> <li><a href="/wiki/Category:Lists_of_isotopes_by_element" title="Category:Lists of isotopes by element">Isotopes by element</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox authority-control" aria-label="Navbox579" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a>: National <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q24638#identifiers" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://d-nb.info/gnd/4147146-5">Germany</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/sh85022201">United States</a></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="https://www.nli.org.il/en/authorities/987007284955005171">Israel</a></span></li></ul></div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; 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