Selected Radioactive Isotopes
Decay modes are [latex]\alpha[/latex], [latex]{\beta }^{-}[/latex], [latex]{\beta }^{+}[/latex], electron capture (EC) and isomeric transition (IT). EC results in the same daughter nucleus as would [latex]{\beta }^{+}[/latex] decay. IT is a transition from a metastable excited state. Energies for [latex]{\beta }^{±}[/latex] decays are the maxima; average energies are roughly one-half the maxima.
Isotope | t1/2 | DecayMode(s) | Energy(MeV) | Percent | [latex]\gamma[/latex]-Ray Energy(MeV) | Percent | |
---|---|---|---|---|---|---|---|
[latex]{\text{}}^{3}\text{H}[/latex] | 12.33 y | [latex]{\beta }^{-}[/latex] | 0.0186 | 100% | |||
[latex]{\text{}}^{14}\text{C}[/latex] | 5730 y | [latex]{\beta }^{-}[/latex] | 0.156 | 100% | |||
[latex]{\text{}}^{13}\text{N}[/latex] | 9.96 min | [latex]{\beta }^{+}[/latex] | 1.20 | 100% | |||
[latex]{\text{}}^{22}\text{Na}[/latex] | 2.602 y | [latex]{\beta }^{+}[/latex] | 0.55 | 90% | [latex]\gamma[/latex] | 1.27 | 100% |
[latex]{\text{}}^{32}\text{P}[/latex] | 14.28 d | [latex]{\beta }^{-}[/latex] | 1.71 | 100% | |||
[latex]{\text{}}^{35}\text{S}[/latex] | 87.4 d | [latex]{\beta }^{-}[/latex] | 0.167 | 100% | |||
[latex]{\text{}}^{36}\text{Cl}[/latex] | [latex]3\text{.}\text{00}×{\text{10}}^{5}\text{y}[/latex] | [latex]{\beta }^{-}[/latex] | 0.710 | 100% | |||
[latex]{\text{}}^{40}\text{K}[/latex] | [latex]1\text{.}\text{28}×{\text{10}}^{9}\text{y}[/latex] | [latex]{\beta }^{-}[/latex] | 1.31 | 89% | |||
[latex]{\text{}}^{43}\text{K}[/latex] | 22.3 h | [latex]{\beta }^{-}[/latex] | 0.827 | 87% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.373 | 87% |
0.618 | 87% | ||||||
[latex]{\text{}}^{45}\text{Ca}[/latex] | 165 d | [latex]{\beta }^{-}[/latex] | 0.257 | 100% | |||
[latex]{\text{}}^{51}\text{Cr}[/latex] | 27.70 d | EC | [latex]\gamma[/latex] | 0.320 | 10% | ||
[latex]{\text{}}^{52}\text{Mn}[/latex] | 5.59d | [latex]{\beta }^{+}[/latex] | 3.69 | 28% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 1.33 | 28% |
1.43 | 28% | ||||||
[latex]{\text{}}^{52}\text{Fe}[/latex] | 8.27 h | [latex]{\beta }^{+}[/latex] | 1.80 | 43% | 0.169 | 43% | |
0.378 | 43% | ||||||
[latex]{\text{}}^{59}\text{Fe}[/latex] | 44.6 d | [latex]{\beta }^{-}\text{s}[/latex] | 0.273 | 45% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 1.10 | 57% |
0.466 | 55% | 1.29 | 43% | ||||
[latex]{\text{}}^{60}\text{Co}[/latex] | 5.271 y | [latex]{\beta }^{-}[/latex] | 0.318 | 100% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 1.17 | 100% |
1.33 | 100% | ||||||
[latex]{\text{}}^{65}\text{Zn}[/latex] | 244.1 d | EC | [latex]\gamma[/latex] | 1.12 | 51% | ||
[latex]{\text{}}^{67}\text{Ga}[/latex] | 78.3 h | EC | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.0933 | 70% | ||
0.185 | 35% | ||||||
0.300 | 19% | ||||||
others | |||||||
[latex]{\text{}}^{75}\text{Se}[/latex] | 118.5 d | EC | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.121 | 20% | ||
0.136 | 65% | ||||||
0.265 | 68% | ||||||
0.280 | 20% | ||||||
others | |||||||
[latex]{\text{}}^{86}\text{Rb}[/latex] | 18.8 d | [latex]{\beta }^{-}\text{s}[/latex] | 0.69 | 9% | [latex]\gamma[/latex] | 1.08 | 9% |
1.77 | 91% | ||||||
[latex]{\text{}}^{85}\text{Sr}[/latex] | 64.8 d | EC | [latex]\gamma[/latex] | 0.514 | 100% | ||
[latex]{\text{}}^{90}\text{Sr}[/latex] | 28.8 y | [latex]{\beta }^{-}[/latex] | 0.546 | 100% | |||
[latex]{\text{}}^{90}\text{Y}[/latex] | 64.1 h | [latex]{\beta }^{-}[/latex] | 2.28 | 100% | |||
[latex]{\text{}}^{99m}\text{Tc}[/latex] | 6.02 h | IT | [latex]\gamma[/latex] | 0.142 | 100% | ||
[latex]{\text{}}^{113m}\text{In}[/latex] | 99.5 min | IT | [latex]\gamma[/latex] | 0.392 | 100% | ||
[latex]{\text{}}^{123}\text{I}[/latex] | 13.0 h | EC | [latex]\gamma[/latex] | 0.159 | [latex]\text{≈100%}\text{}[/latex] | ||
[latex]{\text{}}^{131}\text{I}[/latex] | 8.040 d | [latex]{\beta }^{-}\text{s}[/latex] | 0.248 | 7% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.364 | 85% |
0.607 | 93% | others | |||||
others | |||||||
[latex]{\text{}}^{129}\text{Cs}[/latex] | 32.3 h | EC | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.0400 | 35% | ||
0.372 | 32% | ||||||
0.411 | 25% | ||||||
others | |||||||
[latex]{\text{}}^{137}\text{Cs}[/latex] | 30.17 y | [latex]{\beta }^{-}\text{s}[/latex] | 0.511 | 95% | [latex]\gamma[/latex] | 0.662 | 95% |
1.17 | 5% | ||||||
[latex]{\text{}}^{140}\text{Ba}[/latex] | 12.79 d | [latex]{\beta }^{-}[/latex] | 1.035 | [latex]\text{≈100%}\text{}[/latex] | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.030 | 25% |
0.044 | 65% | ||||||
0.537 | 24% | ||||||
others | |||||||
[latex]{\text{}}^{198}\text{Au}[/latex] | 2.696 d | [latex]{\beta }^{-}[/latex] | 1.161 | [latex]\text{≈100%}\text{}[/latex] | [latex]\gamma[/latex] | 0.412 | [latex]\text{≈100%}\text{}[/latex] |
[latex]{\text{}}^{197}\text{Hg}[/latex] | 64.1 h | EC | [latex]\gamma[/latex] | 0.0733 | 100% | ||
[latex]{\text{}}^{210}\text{Po}[/latex] | 138.38 d | [latex]\alpha[/latex] | 5.41 | 100% | |||
[latex]{\text{}}^{226}\text{Ra}[/latex] | [latex]1\text{.}\text{60}×{\text{10}}^{3}\text{y}[/latex] | [latex]\alpha \text{s}[/latex] | 4.68 | 5% | [latex]\gamma[/latex] | 0.186 | 100% |
4.87 | 95% | ||||||
[latex]{\text{}}^{235}\text{U}[/latex] | [latex]7\text{.}\text{038}×{\text{10}}^{8}\text{y}[/latex] | [latex]\alpha[/latex] | 4.68 | [latex]\text{≈100%}\text{}[/latex] | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | numerous | <0.400% |
[latex]{\text{}}^{238}\text{U}[/latex] | [latex]4\text{.}\text{468}×{\text{10}}^{9}\text{y}[/latex] | [latex]\alpha \text{s}[/latex] | 4.22 | 23% | [latex]\gamma[/latex] | 0.050 | 23% |
4.27 | 77% | ||||||
[latex]{\text{}}^{237}\text{Np}[/latex] | [latex]2\text{.}\text{14}×{\text{10}}^{6}\text{y}[/latex] | [latex]\alpha \text{s}[/latex] | numerous | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | numerous | <0.250% | |
4.96 (max.) | |||||||
[latex]{\text{}}^{239}\text{Pu}[/latex] | [latex]2\text{.}\text{41}×{\text{10}}^{4}\text{y}[/latex] | [latex]\alpha \text{s}[/latex] | 5.19 | 11% | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | [latex]7\text{.}5×{\text{10}}^{-5}[/latex] | 73% |
5.23 | 15% | 0.013 | 15% | ||||
5.24 | 73% | 0.052 | 10% | ||||
others | |||||||
[latex]{\text{}}^{243}\text{Am}[/latex] | [latex]7\text{.}\text{37}×{\text{10}}^{3}\text{y}[/latex] | [latex]\alpha \text{s}[/latex] | Max. 5.44 | [latex]\gamma \phantom{\rule{0.10em}{0ex}}\text{s}[/latex] | 0.075 | ||
5.37 | 88% | others | |||||
5.32 | 11% | ||||||
others |