Appendix B 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 ^{\pm}[/latex] decays are the maxima; average energies are roughly one-half the maxima.

Isotope t 1/2 DecayMode(s) Energy(MeV) Percent [latex]\gamma[/latex]-Ray Energy(MeV) Percent
[latex]^{3} \textbf{H}[/latex] 12.33 y [latex]\beta ^{-}[/latex]­ 0.0186 100%
[latex]^{14} \textbf{C}[/latex] 5730 y [latex]\beta ^{-}[/latex] 0.156 100%
[latex]^{13} \textbf{N}[/latex] 9.96 min [latex]\beta ^{+}[/latex] 1.20 100%
[latex]^{22} \text{Na}[/latex] 2.602 y [latex]\beta ^{+}[/latex] 0.55 90% [latex]\gamma[/latex] 1.27 100%
[latex]^{32} \textbf{P}[/latex] 14.28 d [latex]\beta ^{-}[/latex] 1.71 100%
[latex]^{35} \textbf{S}[/latex] 87.4 d [latex]\beta ^{-}[/latex]­ 0.167 100%
[latex]^{36} \text{Cl}[/latex] [latex]3.00 \times 10^5 \text{y}[/latex] [latex]\beta ^{-}[/latex] 0.710 100%
[latex]^{40} \textbf{K}[/latex] [latex]1.28 \times 10^9 \text{y}[/latex] [latex]\beta ^{-}[/latex] 1.31 89%
[latex]^{43} \textbf{K}[/latex] 22.3 h [latex]\beta ^{-}[/latex] 0.827 87% [latex]\gamma \;\text{s}[/latex] 0.373 87%
0.618 87%
[latex]^{45} \text{Ca}[/latex] 165 d [latex]\beta ^{-}[/latex]­ 0.257 100%
[latex]^{51} \text{Cr}[/latex] 27.70 d EC [latex]\gamma[/latex] 0.320 10%
[latex]^{52} \text{Mn}[/latex] 5.59d [latex]\beta ^{+}[/latex] 3.69 28% [latex]\gamma \;\text{s}[/latex] 1.33 28%
1.43 28%
[latex]^{52} \text{Fe}[/latex] 8.27 h [latex]\beta ^{+}[/latex] 1.80 43% 0.169 43%
0.378 43%
[latex]^{59} \text{Fe}[/latex] 44.6 d [latex]\beta ^{-}[/latex] 0.273 45% [latex]\gamma \;\text{s}[/latex] 1.10 57%
0.466 55% 1.29 43%
[latex]^{60} \text{Co}[/latex] 5.271 y [latex]\beta ^{-}[/latex]­ 0.318 100% [latex]\gamma \;\text{s}[/latex] 1.17 100%
1.33 100%
[latex]^{65} \text{Zn}[/latex] 244.1 d EC [latex]\gamma[/latex] 1.12 51%
[latex]^{67} \text{Ga}[/latex] 78.3 h EC [latex]\gamma \;\text{s}[/latex] 0.0933 70%
0.185 35%
0.300 19%
others
[latex]^{75} \text{Se}[/latex] 118.5 d EC [latex]\gamma \;\text{s}[/latex] 0.121 20%
0.136 65%
0.265 68%
0.280 20%
others
[latex]^{86} \text{Rb}[/latex] 18.8 d [latex]\beta ^{-}[/latex] 0.69 9% [latex]\gamma[/latex] 1.08 9%
1.77 91%
[latex]^{85} \text{Sr}[/latex] 64.8 d EC [latex]\gamma[/latex] 0.514 100%
[latex]^{90} \text{Sr}[/latex] 28.8 y [latex]\beta ^{-}[/latex]­ 0.546 100%
[latex]^{90} \textbf{Y}[/latex] 64.1 h [latex]\beta ^{-}[/latex]­ 2.28 100%
[latex]^{99m} \text{Tc}[/latex] 6.02 h IT [latex]\gamma[/latex] 0.142 100%
[latex]^{113m} \text{In}[/latex] 99.5 min IT [latex]\gamma[/latex] 0.392 100%
[latex]^{123} \textbf{I}[/latex] 13.0 h EC [latex]\gamma[/latex] 0.159 [latex]\approx 100 \%[/latex]
[latex]^{131} \textbf{I}[/latex] 8.040 d [latex]\beta ^{-}[/latex] 0.248 7% [latex]\gamma \;\text{s}[/latex] 0.364 85%
0.607 93% others
others
[latex]^{129} \text{Cs}[/latex] 32.3 h EC [latex]\gamma \;\text{s}[/latex] 0.0400 35%
0.372 32%
0.411 25%
others
[latex]^{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]^{140} \text{Ba}[/latex] 12.79 d [latex]\beta ^{-}[/latex] 1.035 [latex]\approx 100 \&[/latex] [latex]\gamma \;\text{s}[/latex] 0.030 25%
0.044 65%
0.537 24%
others
[latex]^{198} \text{Au}[/latex] 2.696 d [latex]\beta ^{-}[/latex]­ 1.161 [latex]\approx 100 \%[/latex] [latex]\gamma[/latex] 0.412 [latex]\approx 100 \%[/latex]
[latex]^{197} \text{Hg}[/latex] 64.1 h EC [latex]\gamma[/latex] 0.0733 100%
[latex]^{210} \text{Po}[/latex] 138.38 d [latex]\alpha[/latex] 5.41 100%
[latex]^{226} \text{Ra}[/latex] [latex]1.60 \times 10^3 \text{y}[/latex] [latex]\alpha \;\text{s}[/latex] 4.68 5% [latex]\gamma[/latex] 0.186 100%
4.87 95%
[latex]^{235} \textbf{U}[/latex] [latex]7.038 \times 10^8 \text{y}[/latex] [latex]\alpha[/latex] 4.68 [latex]\approx 100 \%[/latex] [latex]\gamma \;\text{s}[/latex] numerous <0.400%
[latex]^{238} \textbf{U}[/latex] [latex]4.468 \times 10^9 \text{y}[/latex] [latex]\alpha \;\text{s}[/latex] 4.22 23% [latex]\gamma[/latex] 0.050 23%
4.27 77%
[latex]^{237} \text{Np}[/latex] [latex]2.14 \times 10^6 \text{y}[/latex] [latex]\alpha \;\text{s}[/latex] numerous [latex]\gamma \;\text{s}[/latex] numerous <0.250%
4.96 (max.)
[latex]^{239} \text{Pu}[/latex] [latex]2.41 \times 10^4 \text{y}[/latex] [latex]\alpha \;\text{s}[/latex] 5.19 11% [latex]\gamma \;\text{s}[/latex] [latex]7.5 \times 10^{-5}[/latex] 73%
5.23 15% 0.013 15%
5.24 73% 0.052 10%
others
[latex]^{243} \text{Am}[/latex] [latex]7.37 \times 10^3 \text{y}[/latex] [latex]\alpha \;\text{s}[/latex] Max. 5.44 [latex]\gamma \;\text{s}[/latex] 0.075
5.37 88% others
5.32 11%
others
Table 2. Selected Radioactive Isotopes

 

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