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Isotopes of xenon
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<h2 id="list-of-isotopes">List of isotopes</h2> <table><tbody><tr><th rowspan="2">Nuclide<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a></th><th rowspan="1"><a href="/facts/Atomic_number/bgAr581S"><i>Z</i></a></th><th rowspan="1"><a href="/facts/Neutron_number/eNtwGnVL"><i>N</i></a></th><th rowspan="1"><a href="/facts/Atomic_mass/J1FJY9MV">Isotopic mass</a> (<a href="/facts/Dalton_(unit)/IMATU3vf">Da</a>)<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a><a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a><a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a></th><th rowspan="2"><a href="/facts/Half-life/kGVH8BAB">Half-life</a><a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a><a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a></th><th rowspan="2"><a href="/facts/Decay_mode/Ya6FVjt4">Decaymode</a><a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a><a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a></th><th rowspan="2"><a href="/facts/Decay_product/hT0obfLv">Daughterisotope</a><a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a></th><th rowspan="2"><a href="/facts/Spin_(particle_physics)/4Jvp7e8P">Spin</a> and<a href="/facts/Parity_(physics)/emSbJ4hD">parity</a><a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a><a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a><a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a></th><th colspan="2"><a href="/facts/Natural_abundance/dGjaAwc9">Natural abundance</a> (mole fraction)</th></tr><tr><th colspan="3">Excitation energy</th><th>Normal proportion<a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a></th><th>Range of variation</th></tr><tr><td>108Xe<a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a></td><td>54</td><td>54</td><td>107.95423(41)</td><td>72(35) μs</td><td><a href="/facts/Alpha_decay/rCsHNIUE">α</a></td><td>104Te</td><td>0+</td><td></td><td></td></tr><tr><td>109Xe</td><td>54</td><td>55</td><td>108.95043(32)</td><td>13(2) ms</td><td>α</td><td>105Te</td><td>(7/2+)</td><td></td><td></td></tr><tr><td rowspan="2">110Xe</td><td rowspan="2">54</td><td rowspan="2">56</td><td rowspan="2">109.94426(11)</td><td rowspan="2">93(3) ms</td><td>α (64%)</td><td>106Te</td><td rowspan="2">0+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td><a href="/facts/Beta_decay/vxTBlckp">β+</a> (36%)</td><td>110I</td></tr><tr><td rowspan="2">111Xe</td><td rowspan="2">54</td><td rowspan="2">57</td><td rowspan="2">110.94147(12)#</td><td rowspan="2">740(200) ms</td><td>β+ (89.6%)</td><td>111I</td><td rowspan="2">5/2+#</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>α (10.4%)</td><td>107Te</td></tr><tr><td rowspan="2">112Xe</td><td rowspan="2">54</td><td rowspan="2">58</td><td rowspan="2">111.9355591(89)</td><td rowspan="2">2.7(8) s</td><td>β+ (98.8%)</td><td>112I</td><td rowspan="2">0+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>α (1.2%)</td><td>108Te</td></tr><tr><td rowspan="4">113Xe</td><td rowspan="4">54</td><td rowspan="4">59</td><td rowspan="4">112.9332217(73)</td><td rowspan="4">2.74(8) s</td><td>β+ (92.98%)</td><td>113I</td><td rowspan="4">5/2+#</td><td rowspan="4"></td><td rowspan="4"></td></tr><tr><td>β+, <a href="/facts/Proton_emission/9zxVkBkp">p</a> (7%)</td><td>112Te</td></tr><tr><td>α (?%)</td><td>109Te</td></tr><tr><td>β+, α (~0.007%)</td><td>109Sb</td></tr><tr><td>113mXe</td><td colspan="3">403.6(14) keV</td><td>6.9(3) μs</td><td><a href="/facts/Isomeric_transition/L8DHcqnk">IT</a></td><td>113Xe</td><td>(11/2−)</td><td></td><td></td></tr><tr><td>114Xe</td><td>54</td><td>60</td><td>113.927980(12)</td><td>10.0(4) s</td><td>β+</td><td>114I</td><td>0+</td><td></td><td></td></tr><tr><td rowspan="2">115Xe</td><td rowspan="2">54</td><td rowspan="2">61</td><td rowspan="2">114.926294(13)</td><td rowspan="2">18(3) s</td><td>β+ (99.66%)</td><td>115I</td><td rowspan="2">(5/2+)</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β+, p (0.34%)</td><td>114Te</td></tr><tr><td>116Xe</td><td>54</td><td>62</td><td>115.921581(14)</td><td>59(2) s</td><td>β+</td><td>116I</td><td>0+</td><td></td><td></td></tr><tr><td rowspan="2">117Xe</td><td rowspan="2">54</td><td rowspan="2">63</td><td rowspan="2">116.920359(11)</td><td rowspan="2">61(2) s</td><td>β+</td><td>117I</td><td rowspan="2">5/2+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β+, p (0.0029%)</td><td>116Te</td></tr><tr><td>118Xe</td><td>54</td><td>64</td><td>117.916179(11)</td><td>3.8(9) min</td><td>β+</td><td>118I</td><td>0+</td><td></td><td></td></tr><tr><td rowspan="2">119Xe</td><td rowspan="2">54</td><td rowspan="2">65</td><td rowspan="2">118.915411(11)</td><td rowspan="2">5.8(3) min</td><td>β+ (79%)</td><td>119I</td><td rowspan="2">5/2+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td><a href="/facts/Electron_capture/EIccoV1u">EC</a> (21%)</td><td>119I</td></tr><tr><td>120Xe</td><td>54</td><td>66</td><td>119.911784(13)</td><td>46.0(6) min</td><td>β+</td><td>120I</td><td>0+</td><td></td><td></td></tr><tr><td>121Xe</td><td>54</td><td>67</td><td>120.911453(11)</td><td>40.1(20) min</td><td>β+</td><td>121I</td><td>5/2+</td><td></td><td></td></tr><tr><td>122Xe</td><td>54</td><td>68</td><td>121.908368(12)</td><td>20.1(1) h</td><td><a href="/facts/Electron_capture/EIccoV1u">EC</a></td><td>122I</td><td>0+</td><td></td><td></td></tr><tr><td>123Xe</td><td>54</td><td>69</td><td>122.908482(10)</td><td>2.08(2) h</td><td>β+</td><td>123I</td><td>1/2+</td><td></td><td></td></tr><tr><td>123mXe</td><td colspan="3">185.18(11) keV</td><td>5.49(26) μs</td><td>IT</td><td>123Xe</td><td>7/2−</td><td></td><td></td></tr><tr><td>124Xe<a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a></td><td>54</td><td>70</td><td>123.9058852(15)</td><td>1.8(5 (<a href="/facts/Statistical_error/Ef0LgAS4">stat</a>), 1 (<a href="/facts/Systematic_error/q7pa7bRt">sys</a>))×1022 y<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a></td><td><a href="/facts/Double_electron_capture/aQ1ElH3c">Double EC</a></td><td>124Te</td><td>0+</td><td>9.5(5)×10−4</td><td></td></tr><tr><td>125Xe</td><td>54</td><td>71</td><td>124.9063876(15)</td><td>16.87(8) h</td><td>EC / β+</td><td>125I</td><td>1/2+</td><td></td><td></td></tr><tr><td>125m1Xe</td><td colspan="3">252.61(14) keV</td><td>56.9(9) s</td><td>IT</td><td>125Xe</td><td>9/2−</td><td></td><td></td></tr><tr><td>125m2Xe</td><td colspan="3">295.89(15) keV</td><td>0.14(3) μs</td><td>IT</td><td>125Xe</td><td>7/2+</td><td></td><td></td></tr><tr><td>126Xe</td><td>54</td><td>72</td><td>125.904297422(6)</td><td colspan="3"><a href="/facts/Observationally_Stable/vC0VVvqN">Observationally Stable</a><a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a></td><td>0+</td><td>8.9(3)×10−4</td><td></td></tr><tr><td>127Xe</td><td>54</td><td>73</td><td>126.9051836(44)</td><td>36.342(3) d</td><td>EC</td><td>127I</td><td>1/2+</td><td></td><td></td></tr><tr><td>127mXe</td><td colspan="3">297.10(8) keV</td><td>69.2(9) s</td><td>IT</td><td>127Xe</td><td>9/2−</td><td></td><td></td></tr><tr><td>128Xe</td><td>54</td><td>74</td><td>127.9035307534(56)</td><td colspan="3">Stable</td><td>0+</td><td>0.01910(13)</td><td></td></tr><tr><td>128mXe</td><td colspan="3">2787.2(3) keV</td><td>83(2) ns</td><td>IT</td><td>128Xe</td><td>8−</td><td></td><td></td></tr><tr><td>129Xe<a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a></td><td>54</td><td>75</td><td>128.9047808574(54)</td><td colspan="3">Stable</td><td>1/2+</td><td>0.26401(138)</td><td></td></tr><tr><td>129mXe</td><td colspan="3">236.14(3) keV</td><td>8.88(2) d</td><td>IT</td><td>129Xe</td><td>11/2−</td><td></td><td></td></tr><tr><td>130Xe</td><td>54</td><td>76</td><td>129.903509346(10)</td><td colspan="3">Stable</td><td>0+</td><td>0.04071(22)</td></tr><tr><td>131Xe<a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a></td><td>54</td><td>77</td><td>130.9050841281(55)</td><td colspan="3">Stable</td><td>3/2+</td><td>0.21232(51)</td><td></td></tr><tr><td>131mXe</td><td colspan="3">163.930(8) keV</td><td>11.948(12) d</td><td>IT</td><td>131Xe</td><td>11/2−</td><td></td><td></td></tr><tr><td>132Xe<a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a></td><td>54</td><td>78</td><td>131.9041550835(54)</td><td colspan="3">Stable</td><td>0+</td><td>0.26909(55)</td><td></td></tr><tr><td>132mXe</td><td colspan="3">2752.21(17) keV</td><td>8.39(11) ms</td><td>IT</td><td>132Xe</td><td>(10+)</td><td></td><td></td></tr><tr><td>133Xe<a class="footnote-ref" id="fnref:30" href="#fn:30"><sup>30</sup></a><a class="footnote-ref" id="fnref:31" href="#fn:31"><sup>31</sup></a></td><td>54</td><td>79</td><td>132.9059107(26)</td><td>5.2474(5) d</td><td>β−</td><td>133Cs</td><td>3/2+</td><td></td><td></td></tr><tr><td>133m1Xe</td><td colspan="3">233.221(15) keV</td><td>2.198(13) d</td><td>IT</td><td>133Xe</td><td>11/2−</td><td></td><td></td></tr><tr><td>133m2Xe</td><td colspan="3">2147(20)# keV</td><td>8.64(13) ms</td><td>IT</td><td>133Xe</td><td>(23/2+)</td><td></td><td></td></tr><tr><td>134Xe<a class="footnote-ref" id="fnref:32" href="#fn:32"><sup>32</sup></a></td><td>54</td><td>80</td><td>133.905393030(6)</td><td colspan="3">Observationally Stable<a class="footnote-ref" id="fnref:33" href="#fn:33"><sup>33</sup></a></td><td>0+</td><td>0.10436(35)</td><td></td></tr><tr><td>134m1Xe</td><td colspan="3">1965.5(5) keV</td><td>290(17) ms</td><td>IT</td><td>134Xe</td><td>7−</td><td></td><td></td></tr><tr><td>134m2Xe</td><td colspan="3">3025.2(15) keV</td><td>5(1) μs</td><td>IT</td><td>134Xe</td><td>(10+)</td><td></td><td></td></tr><tr><td><a href="/facts/Xenon-135/vU9yqxK4">135Xe</a><a class="footnote-ref" id="fnref:34" href="#fn:34"><sup>34</sup></a></td><td>54</td><td>81</td><td>134.9072314(39)</td><td>9.14(2) h</td><td>β−</td><td>135Cs</td><td>3/2+</td><td></td><td></td></tr><tr><td rowspan="2">135mXe</td><td rowspan="2" colspan="3">526.551(13) keV</td><td rowspan="2">15.29(5) min</td><td>IT (99.70%)</td><td>135Xe</td><td rowspan="2">11/2−</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β− (0.30%)</td><td>135Cs</td></tr><tr><td>136Xe<a class="footnote-ref" id="fnref:35" href="#fn:35"><sup>35</sup></a></td><td>54</td><td>82</td><td>135.907214474(7)</td><td>2.18(5)×1021 y</td><td>β−β−</td><td>136Ba</td><td>0+</td><td>0.08857(72)</td><td></td></tr><tr><td>136mXe</td><td colspan="3">1891.74(7) keV</td><td>2.92(3) μs</td><td>IT</td><td><i>136Xe</i></td><td>6+</td><td></td><td></td></tr><tr><td>137Xe</td><td>54</td><td>83</td><td>136.91155777(11)</td><td>3.818(13) min</td><td>β−</td><td>137Cs</td><td>7/2−</td><td></td><td></td></tr><tr><td>138Xe</td><td>54</td><td>84</td><td>137.9141463(30)</td><td>14.14(7) min</td><td>β−</td><td>138Cs</td><td>0+</td><td></td><td></td></tr><tr><td>139Xe</td><td>54</td><td>85</td><td>138.9187922(23)</td><td>39.68(14) s</td><td>β−</td><td>139Cs</td><td>3/2−</td><td></td><td></td></tr><tr><td>140Xe</td><td>54</td><td>86</td><td>139.9216458(25)</td><td>13.60(10) s</td><td>β−</td><td>140Cs</td><td>0+</td><td></td><td></td></tr><tr><td rowspan="2">141Xe</td><td rowspan="2">54</td><td rowspan="2">87</td><td rowspan="2">140.9267872(31)</td><td rowspan="2">1.73(1) s</td><td>β− (99.96%)</td><td>141Cs</td><td rowspan="2">5/2−</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, <a href="/facts/Neutron_emission/lXLQRDCQ">n</a> (0.044%)</td><td>140Cs</td></tr><tr><td rowspan="2">142Xe</td><td rowspan="2">54</td><td rowspan="2">88</td><td rowspan="2">141.9299731(29)</td><td rowspan="2">1.23(2) s</td><td>β− (99.63%)</td><td>142Cs</td><td rowspan="2">0+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (0.37%)</td><td>141Cs</td></tr><tr><td rowspan="2">143Xe</td><td rowspan="2">54</td><td rowspan="2">89</td><td rowspan="2">142.9353696(50)</td><td rowspan="2">511(6) ms</td><td>β− (99.00%)</td><td>143Cs</td><td rowspan="2">5/2−</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (1.00%)</td><td>142Cs</td></tr><tr><td rowspan="2">144Xe</td><td rowspan="2">54</td><td rowspan="2">90</td><td rowspan="2">143.9389451(57)</td><td rowspan="2">0.388(7) s</td><td>β− (97.0%)</td><td>144Cs</td><td rowspan="2">0+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (3.0%)</td><td>143Cs</td></tr><tr><td rowspan="2">145Xe</td><td rowspan="2">54</td><td rowspan="2">91</td><td rowspan="2">144.944720(12)</td><td rowspan="2">188(4) ms</td><td>β− (95.0%)</td><td>145Cs</td><td rowspan="2">3/2−#</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (5.0%)</td><td>144Cs</td></tr><tr><td rowspan="2">146Xe</td><td rowspan="2">54</td><td rowspan="2">92</td><td rowspan="2">145.948518(26)</td><td rowspan="2">146(6) ms</td><td>β−</td><td>146Cs</td><td rowspan="2">0+</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (6.9%)</td><td>145Cs</td></tr><tr><td rowspan="2">147Xe</td><td rowspan="2">54</td><td rowspan="2">93</td><td rowspan="2">146.95448(22)#</td><td rowspan="2">88(14) ms</td><td>β− (>92%)</td><td>147Cs</td><td rowspan="2">3/2−#</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>β−, n (<8%)</td><td>146Cs</td></tr><tr><td>148Xe</td><td>54</td><td>94</td><td>147.95851(32)#</td><td>85(15) ms</td><td>β−</td><td>148Cs</td><td>0+</td><td></td><td></td></tr><tr><td>149Xe</td><td>54</td><td>95</td><td>148.96457(32)#</td><td>50# ms[>550 ms]</td><td></td><td></td><td>3/2−#</td><td></td><td></td></tr><tr><td>150Xe</td><td>54</td><td>96</td><td>149.96888(32)#</td><td>40# ms[>550 ns]]</td><td></td><td></td><td>0+</td><td></td><td></td></tr><tr><th colspan="20"><i>This table header & footer:</i> <ul><li>view</li></ul></th></tr></tbody></table> <ul><li>The isotopic composition refers to that in air.</li></ul> <h2 id="xenon-124">Xenon-124</h2> <p>Xenon-124 is an isotope of xenon that undergoes double electron capture to <a href="/facts/Tellurium/v7QvfIvS">tellurium</a>-124 with a very long half-life of 1.8×1022 years, more than 12 orders of magnitude longer than the age of the universe ((13.799±0.021)×109 years). Such decays have been observed in the <a href="/facts/XENON/qtYSMPeE">XENON1T</a> detector in 2019, and are the rarest processes ever directly observed.<a class="footnote-ref" id="fnref:36" href="#fn:36"><sup>36</sup></a> (Even slower decays of other nuclei have been measured, but by detecting decay products that have accumulated over billions of years rather than observing them directly.<a class="footnote-ref" id="fnref:37" href="#fn:37"><sup>37</sup></a>) </p> <h2 id="xenon-133">Xenon-133</h2> <p>Xenon-133 (sold as a drug under the brand name <i>Xeneisol</i>, <a href="/facts/ATC_code/gcFTwqSA">ATC code</a> <a href="/facts/ATC_code_V09/LuMkD1C1">V09EX03</a> (<a href="https://www.whocc.no/atc_ddd_index/?code=V09EX03">WHO</a>)) is an isotope of xenon. It is a <a href="/facts/Radionuclide/5WpCfbdq">radionuclide</a> that is <a href="/facts/Ventilation/perfusion_scan/PxMVR85U">inhaled</a> to assess pulmonary function, and to image the <a href="/facts/Lung/gTWXI6Fj">lungs</a>.<a class="footnote-ref" id="fnref:38" href="#fn:38"><sup>38</sup></a> It is also used to image blood flow, particularly in the <a href="/facts/Brain/EKla9NkJ">brain</a>.<a class="footnote-ref" id="fnref:39" href="#fn:39"><sup>39</sup></a> 133Xe is also an important <a href="/facts/Fission_product/xJd9MXXH">fission product</a>. It is discharged to the atmosphere in small quantities by some nuclear power plants.<a class="footnote-ref" id="fnref:40" href="#fn:40"><sup>40</sup></a> </p> <h2 id="xenon-135">Xenon-135</h2> <p class="note">Main article: <a href="/facts/Xenon-135/vU9yqxK4">Xenon-135</a></p> <p>Xenon-135 is a <a href="/facts/Radioactive_isotope/5WpCfbdq">radioactive isotope</a> of <a href="/facts/Xenon/9E3XR69R">xenon</a>, produced as a <a href="/facts/Fission_product/xJd9MXXH">fission product</a> of uranium. It has a <a href="/facts/Half-life/kGVH8BAB">half-life</a> of about 9.2 hours and is the most powerful known <a href="/facts/Neutron/oRCM1geb">neutron</a>-absorbing <a href="/facts/Nuclear_poison/bkruR3yz">nuclear poison</a> (having a <a href="/facts/Neutron_cross_section/gAkJmXXA">neutron absorption cross-section</a> of 2 million <a href="/facts/Barn_(unit)/0yCEtKJ9">barns</a><a class="footnote-ref" id="fnref:41" href="#fn:41"><sup>41</sup></a>). The overall yield of xenon-135 from fission is 6.3%, though most of this results from the radioactive decay of fission-produced <a href="/facts/Tellurium-135/cE0X04xU">tellurium-135</a> and <a href="/facts/Iodine-135/HxgH1yJD">iodine-135</a>. Xe-135 exerts a significant effect on <a href="/facts/Nuclear_reactor/8xqjIbge">nuclear reactor</a> operation (<a href="/facts/Xenon_pit/IH2mYTyp">xenon pit</a>). It is discharged to the atmosphere in small quantities by some nuclear power plants.<a class="footnote-ref" id="fnref:42" href="#fn:42"><sup>42</sup></a> </p> <h2 id="xenon-136">Xenon-136</h2> <p>Xenon-136 is an isotope of xenon that undergoes <a href="/facts/Double_beta_decay/ILmpbfqS">double beta decay</a> to <a href="/facts/Barium/IkL09XHQ">barium</a>-136 with a very long half-life of 2.11×1021 years, more than 10 orders of magnitude longer than the age of the universe ((13.799±0.021)×109 years). It is being used in the <a href="/facts/Enriched_Xenon_Observatory/QKTChNvL">Enriched Xenon Observatory</a> experiment to search for <a href="/facts/Neutrinoless_double_beta_decay/7u36G9d4">neutrinoless double beta decay</a>. </p> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Xenon_isotope_geochemistry/UBQoKQKh">Xenon isotope geochemistry</a></li></ul> <ul><li>Isotope masses from <a href="http://amdc.in2p3.fr/web/masseval.html">Ame2003 Atomic Mass Evaluation</a> by Georges Audi, Aaldert Hendrik Wapstra, Catherine Thibault, Jean Blachot and Olivier Bersillon in <i>Nuclear Physics</i> A729 (2003).</li> <li>Isotopic compositions and standard atomic masses from: <ul><li><a href="/facts/John_Robert_de_Laeter/jYQj55GI">de Laeter, John Robert</a>; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). <a href="https://doi.org/10.1351%2Fpac200375060683">"Atomic weights of the elements. Review 2000 (IUPAC Technical Report)"</a>. <i><a href="/facts/Pure_and_Applied_Chemistry/9QdCDKxf">Pure and Applied Chemistry</a></i>. 75 (6): 683–800. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1351%2Fpac200375060683">10.1351/pac200375060683</a>.</li> <li>Wieser, Michael E. (2006). <a href="https://doi.org/10.1351%2Fpac200678112051">"Atomic weights of the elements 2005 (IUPAC Technical Report)"</a>. <i><a href="/facts/Pure_and_Applied_Chemistry/9QdCDKxf">Pure and Applied Chemistry</a></i>. 78 (11): 2051–2066. <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1351%2Fpac200678112051">10.1351/pac200678112051</a>.</li></ul></li> <li><a href="http://old.iupac.org/news/archives/2005/atomic-weights_revised05.html">"News & Notices: Standard Atomic Weights Revised"</a>. <i>International Union of Pure and Applied Chemistry</i>. 19 October 2005.</li> <li>Half-life, spin, and isomer data selected from the following sources. <ul><li>Audi, Georges; Bersillon, Olivier; Blachot, Jean; <a href="/facts/Aaldert_Wapstra/9Ylvt18s">Wapstra, Aaldert Hendrik</a> (2003), <a href="https://hal.archives-ouvertes.fr/in2p3-00020241/document">"The NUBASE evaluation of nuclear and decay properties"</a>, <i>Nuclear Physics A</i>, 729: 3–128, <a href="/facts/Bibcode_(identifier)/9HtdQSGB">Bibcode</a>:<a href="https://ui.adsabs.harvard.edu/abs/2003NuPhA.729....3A">2003NuPhA.729....3A</a>, <a href="/facts/Doi_(identifier)/muM9Etpq">doi</a>:<a href="https://doi.org/10.1016%2Fj.nuclphysa.2003.11.001">10.1016/j.nuclphysa.2003.11.001</a></li> <li><a href="/facts/National_Nuclear_Data_Center/SgVzvxLk">National Nuclear Data Center</a>. <a href="http://www.nndc.bnl.gov/nudat2/">"NuDat 2.x database"</a>. <a href="/facts/Brookhaven_National_Laboratory/L2JrG0K1">Brookhaven National Laboratory</a>.</li> <li>Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). <i><a href="/facts/CRC_Handbook_of_Chemistry_and_Physics/qjxzC2Cu">CRC Handbook of Chemistry and Physics</a></i> (85th ed.). <a href="/facts/Boca_Raton,_Florida/9gcNen3S">Boca Raton, Florida</a>: <a href="/facts/CRC_Press/duTuH4hz">CRC Press</a>. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-8493-0485-9.</li></ul></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"Observation of two-neutrino double electron capture in 124Xe with XENON1T". Nature. 568 (7753): 532–535. 2019. doi:10.1038/s41586-019-1124-4. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Albert, J. B.; Auger, M.; Auty, D. J.; Barbeau, P. S.; Beauchamp, E.; Beck, D.; Belov, V.; Benitez-Medina, C.; Bonatt, J.; Breidenbach, M.; Brunner, T.; Burenkov, A.; Cao, G. F.; Chambers, C.; Chaves, J.; Cleveland, B.; Cook, S.; Craycraft, A.; Daniels, T.; Danilov, M.; Daugherty, S. J.; Davis, C. G.; Davis, J.; Devoe, R.; Delaquis, S.; Dobi, A.; Dolgolenko, A.; Dolinski, M. J.; Dunford, M.; et al. (2014). "Improved measurement of the 2νββ half-life of 136Xe with the EXO-200 detector". Physical Review C. 89 (1): 015502. arXiv:1306.6106. Bibcode:2014PhRvC..89a5502A. doi:10.1103/PhysRevC.89.015502. Archived from the original on 2023-06-13. Retrieved 2023-01-24. <a href="https://web.archive.org/web/20230613193026/https://authors.library.caltech.edu/44641/" target="_blank">https://web.archive.org/web/20230613193026/https://authors.library.caltech.edu/44641/</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Wang, M.; Audi, G.; Kondev, F. G.; Huang, W. J.; Naimi, S.; Xu, X. (2017). "The AME2016 atomic mass evaluation (II). Tables, graphs, and references" (PDF). Chinese Physics C. 41 (3): 030003-1 – 030003-442. doi:10.1088/1674-1137/41/3/030003. <a href="http://nuclearmasses.org/resources_folder/Wang_2017_Chinese_Phys_C_41_030003.pdf" target="_blank">http://nuclearmasses.org/resources_folder/Wang_2017_Chinese_Phys_C_41_030003.pdf</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Status of ββ-decay in Xenon, Roland Lüscher, accessed online September 17, 2007. Archived September 27, 2007, at the Wayback Machine <a href="http://www.shef.ac.uk/physics/bus2006/talks/luscher_roland.pdf" target="_blank">http://www.shef.ac.uk/physics/bus2006/talks/luscher_roland.pdf</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Barros, N.; Thurn, J.; Zuber, K. (2014). "Double beta decay searches of 134Xe, 126Xe, and 124Xe with large scale Xe detectors". Journal of Physics G. 41 (11): 115105–1–115105–12. arXiv:1409.8308. Bibcode:2014JPhG...41k5105B. doi:10.1088/0954-3899/41/11/115105. S2CID 116264328. <a href="/wiki/Journal_of_Physics_G" target="_blank">/wiki/Journal_of_Physics_G</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Yan, X.; Cheng, Z.; Abdukerim, A.; et al. (2024). "Searching for two-neutrino and neutrinoless double beta decay of 134Xe with the PandaX-4T experiment". Physical Review Letters. 132 (152502). arXiv:2312.15632. doi:10.1103/PhysRevLett.132.152502. <a href="/wiki/ArXiv_(identifier)" target="_blank">/wiki/ArXiv_(identifier)</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Auranen, K.; et al. (2018). "Superallowed α decay to doubly magic 100Sn" (PDF). Physical Review Letters. 121 (18): 182501. Bibcode:2018PhRvL.121r2501A. doi:10.1103/PhysRevLett.121.182501. PMID 30444390. <a href="https://www.pure.ed.ac.uk/ws/files/77942573/PhysRevLett.121.pdf" target="_blank">https://www.pure.ed.ac.uk/ws/files/77942573/PhysRevLett.121.pdf</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Boulos, M. S.; Manuel, O. K. (1971). "The xenon record of extinct radioactivities in the Earth". Science. 174 (4016): 1334–1336. Bibcode:1971Sci...174.1334B. doi:10.1126/science.174.4016.1334. PMID 17801897. S2CID 28159702. <a href="/wiki/Science_(journal)" target="_blank">/wiki/Science_(journal)</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Ardoin, L.; Broadley, M.W.; Almayrac, M.; Avice, G.; Byrne, D.J.; Tarantola, A.; Lepland, A.; Saito, T.; Komiya, T.; Shibuya, T.; Marty, B. (2022). "The end of the isotopic evolution of atmospheric xenon". Geochemical Perspectives Letters. 20: 43–47. Bibcode:2022GChPL..20...43A. doi:10.7185/geochemlet.2207. S2CID 247399987. <a href="https://doi.org/10.7185%2Fgeochemlet.2207" target="_blank">https://doi.org/10.7185%2Fgeochemlet.2207</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>mXe – Excited nuclear isomer. <a href="/wiki/Nuclear_isomer" target="_blank">/wiki/Nuclear_isomer</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits. <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p># – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS). <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>Bold half-life – nearly stable, half-life longer than age of universe. <a href="/wiki/Age_of_universe" target="_blank">/wiki/Age_of_universe</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>Modes of decay: EC:Electron captureIT:Isomeric transitionn:Neutron emission <a href="/wiki/Electron_capture" target="_blank">/wiki/Electron_capture</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>Bold symbol as daughter – Daughter product is stable. <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> <li id="fn:20"><p>( ) spin value – Indicates spin with weak assignment arguments. <a href="#fnref:20" class="footnote-back-ref">↩</a></p></li> <li id="fn:21"><p># – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). <a href="#fnref:21" class="footnote-back-ref">↩</a></p></li> <li id="fn:22"><p>Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae. <a href="https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf" target="_blank">https://www-nds.iaea.org/amdc/ame2020/NUBASE2020.pdf</a> <a href="#fnref:22" class="footnote-back-ref">↩</a></p></li> <li id="fn:23"><p>Heaviest known isotope with equal numbers of protons and neutrons <a href="#fnref:23" class="footnote-back-ref">↩</a></p></li> <li id="fn:24"><p>Primordial radionuclide <a href="/wiki/Primordial_nuclide" target="_blank">/wiki/Primordial_nuclide</a> <a href="#fnref:24" class="footnote-back-ref">↩</a></p></li> <li id="fn:25"><p>"Observation of two-neutrino double electron capture in 124Xe with XENON1T". Nature. 568 (7753): 532–535. 2019. doi:10.1038/s41586-019-1124-4. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:25" class="footnote-back-ref">↩</a></p></li> <li id="fn:26"><p>Suspected of undergoing DEC decay to 126Te <a href="#fnref:26" class="footnote-back-ref">↩</a></p></li> <li id="fn:27"><p>Used in a method of radiodating groundwater and to infer certain events in the Solar System's history <a href="/wiki/Iodine-129#Applications" target="_blank">/wiki/Iodine-129#Applications</a> <a href="#fnref:27" class="footnote-back-ref">↩</a></p></li> <li id="fn:28"><p>Fission product <a href="/wiki/Fission_product" target="_blank">/wiki/Fission_product</a> <a href="#fnref:28" class="footnote-back-ref">↩</a></p></li> <li id="fn:29"><p>Fission product <a href="/wiki/Fission_product" target="_blank">/wiki/Fission_product</a> <a href="#fnref:29" class="footnote-back-ref">↩</a></p></li> <li id="fn:30"><p>Fission product <a href="/wiki/Fission_product" target="_blank">/wiki/Fission_product</a> <a href="#fnref:30" class="footnote-back-ref">↩</a></p></li> <li id="fn:31"><p>Has medical uses <a href="/wiki/Nuclear_medicine" target="_blank">/wiki/Nuclear_medicine</a> <a href="#fnref:31" class="footnote-back-ref">↩</a></p></li> <li id="fn:32"><p>Fission product <a href="/wiki/Fission_product" target="_blank">/wiki/Fission_product</a> <a href="#fnref:32" class="footnote-back-ref">↩</a></p></li> <li id="fn:33"><p>Theoretically capable of undergoing β−β− decay to 134Ba with a half-life over 2.8×1022 years[11] <a href="#fnref:33" class="footnote-back-ref">↩</a></p></li> <li id="fn:34"><p>Most powerful known neutron absorber, produced in nuclear power plants as a decay product of 135I, itself a decay product of 135Te, a fission product. Normally absorbs neutrons in the high neutron flux environments to become 136Xe; see iodine pit for more information <a href="/wiki/Neutron_absorber" target="_blank">/wiki/Neutron_absorber</a> <a href="#fnref:34" class="footnote-back-ref">↩</a></p></li> <li id="fn:35"><p>Primordial radionuclide <a href="/wiki/Primordial_nuclide" target="_blank">/wiki/Primordial_nuclide</a> <a href="#fnref:35" class="footnote-back-ref">↩</a></p></li> <li id="fn:36"><p>David Nield (26 Apr 2019). "A Dark Matter Detector Just Recorded One of The Rarest Events Known to Science". <a href="https://www.sciencealert.com/a-dark-matter-detector-just-detected-one-of-the-rarest-events-ever-in-science" target="_blank">https://www.sciencealert.com/a-dark-matter-detector-just-detected-one-of-the-rarest-events-ever-in-science</a> <a href="#fnref:36" class="footnote-back-ref">↩</a></p></li> <li id="fn:37"><p>Hennecke, Edward W.; Manuel, O. K.; Sabu, Dwarka D. (1975). "Double beta decay of Te 128". Physical Review C. 11 (4): 1378–1384. doi:10.1103/PhysRevC.11.1378. <a href="http://scholarsmine.mst.edu/cgi/viewcontent.cgi?article=2240&context=chem_facwork" target="_blank">http://scholarsmine.mst.edu/cgi/viewcontent.cgi?article=2240&context=chem_facwork</a> <a href="#fnref:37" class="footnote-back-ref">↩</a></p></li> <li id="fn:38"><p>Jones, R. L.; Sproule, B. J.; Overton, T. R. (1978). "Measurement of regional ventilation and lung perfusion with Xe-133". Journal of Nuclear Medicine. 19 (10): 1187–1188. PMID 722337. <a href="/wiki/PMID_(identifier)" target="_blank">/wiki/PMID_(identifier)</a> <a href="#fnref:38" class="footnote-back-ref">↩</a></p></li> <li id="fn:39"><p>Hoshi, H.; Jinnouchi, S.; Watanabe, K.; Onishi, T.; Uwada, O.; Nakano, S.; Kinoshita, K. (1987). "Cerebral blood flow imaging in patients with brain tumor and arterio-venous malformation using Tc-99m hexamethylpropylene-amine oxime--a comparison with Xe-133 and IMP". Kaku Igaku. 24 (11): 1617–1623. PMID 3502279. <a href="/wiki/PMID_(identifier)" target="_blank">/wiki/PMID_(identifier)</a> <a href="#fnref:39" class="footnote-back-ref">↩</a></p></li> <li id="fn:40"><p>Effluent Releases from Nuclear Power Plants and Fuel-Cycle Facilities. National Academies Press (US). 2012-03-29. <a href="https://www.ncbi.nlm.nih.gov/books/NBK201991/" target="_blank">https://www.ncbi.nlm.nih.gov/books/NBK201991/</a> <a href="#fnref:40" class="footnote-back-ref">↩</a></p></li> <li id="fn:41"><p>Chart of the Nuclides 13th Edition <a href="#fnref:41" class="footnote-back-ref">↩</a></p></li> <li id="fn:42"><p>Effluent Releases from Nuclear Power Plants and Fuel-Cycle Facilities. National Academies Press (US). 2012-03-29. <a href="https://www.ncbi.nlm.nih.gov/books/NBK201991/" target="_blank">https://www.ncbi.nlm.nih.gov/books/NBK201991/</a> <a href="#fnref:42" class="footnote-back-ref">↩</a></p></li> </ol>