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# College Physics

Science and Technology

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