# Activation product

An activation product is a material that has been made radioactive by the process of neutron activation.
Fission products and actinides produced by neutron absorption of nuclear fuel itself are normally referred to by those specific names, and activation product reserved for products of neutron capture by other materials, such as structural components of the nuclear reactor or nuclear bomb, the reactor coolant, control rods or other neutron poisons, or materials in the environment. All of these, however, need to be handled as radioactive waste. Some nuclides originate in more than one way, as activation products or fission products.
Activation products in a reactor's primary coolant loop are a main reason reactors use a chain of two or even three coolant loops linked by heat exchangers.
Fusion reactors will not produce radioactive waste from the fusion product nuclei themselves, which are normally just helium-4, but generate high neutron fluxes, so activation products are a particular concern.
Activation product radionuclides include:
Half-lives and decay branching fractions for activation products :
| Nuclide | Half-life | Decay mode | branching fraction | Source | Notes |
| $^3$ $_1$H | 12.312 ± 0.025 y | β$^−$ | 1.0 | LNHB |
| $^{10}$ $_4$Be | ( 1.51 ± 0.06 ) x 10$^6$ y | β$^−$ | 1.0 | ENSDF |
| $^{14}$ $_6$C | ( 5.7 ± 0.03 ) x 10$^3$ y | β$^−$ | 1.0 | LNHB |
| $^{15}$ $_6$C | 2.449 ± 0.005 s | β$^−$ | 1.0 | ENSDF |
| $^{16}$ $_7$N | 7.13 ± 0.02 s | β$^−$ | 1.0 | ENSDF |
| $^{19}$ $_8$O | 26.88 ± 0.05 s | β$^−$ | 1.0 | ENSDF |
| $^{22}$ $_{11}$Na | 950.57 ± 0.23 d | EC | 0.1011 ± 0.0002a | IAEA-CRP-XG | [1] |
| $^{22}$ $_{11}$Na | 950.57 ± 0.23 d | β$^+$ | 0.8989 ± 0.0002a | IAEA-CRP-XG | [1] |
| $^{24}$ $_{11}$Na | 0.62329 ± 0.00006 d | β$^−$ | 1.0 | IAEA-CRP-XG |
| $^{27}$ $_{12}$Mg | 9.458 ± 0.012 m | β$^−$ | 1.0 | ENSDF |
| $^{26}$ $_{13}$Al | ( 7.17 ± 0.24 ) x 10$^5$ y | EC | 0.1825 ± 0.0023b | LNHB | [2] |
| $^{26}$ $_{13}$Al | ( 7.17 ± 0.24 ) x 10$^5$ y | β$^+$ | 0.8175 ± 0.0023b | LNHB | [2] |
| $^{35}$ $_{16}$S | 87.32 ± 0.16 d | β$^−$ | 1.0 | LNHB |
| $^{36}$ $_{17}$Cl | ( 0.01 ± 0.03 ) x 10$^5$ y | EC | 0.019 ± 0.001 | LNHB |
| $^{36}$ $_{17}$Cl | ( 0.01 ± 0.03 ) x 10$^5$ y | β$^−$ | 0.981 ± 0.001 | LNHB |
| $^{39}$ $_{18}$Ar | 269 ± 3 y | β$^−$ | 1.0 | ENSDF |
| $^{41}$ $_{18}$Ar | 109.61 ± 0.04 m | β$^−$ | 1.0 | ENSDF |
| $^{40}$ $_{19}$K | ( 4.563 ± 0.013 ) x 10$^{11}$ d | EC | 0.1086 ± 0.0013a | IAEA-CRP-XG | [1] |
| $^{40}$ $_{19}$K | ( 4.563 ± 0.013 ) x 10$^{11}$ d | β$^−$ | 0.8914 ± 0.0013a | IAEA-CRP-XG | [1] |
| $^{42}$ $_{19}$K | 12.36 ± 0.012 h | β$^−$ | 1.0 | ENSDF |
| $^{41}$ $_{20}$Ca | ( 1.02 ± 0.07 ) x 10$^5$ y | EC | 1.0 | ENSDF |
| $^{45}$ $_{20}$Ca | 162.61 ± 0.09 d | β$^−$ | 1.0 | ENSDF |
| $^{47}$ $_{21}$Sc | 3.3492 ± 0.0006 d | β$^−$ | 1.0 | ENSDF |
| $^{48}$ $_{21}$Sc | 43.67 ± 0.09 h | β$^−$ | 1.0 | ENSDF |
| $^{51}$ $_{24}$Cr | 27.7009 ± 0.002 d | EC | 1.0 | IAEA-CRP-XG |
| $^{54}$ $_{25}$Mn | 312.29 ± 0.26 d | EC | 1.0 | IAEA-CRP-XG |
| $^{56}$ $_{25}$Mn | 0.107449 ± 0.000019 d | β$^−$ | 1.0 | IAEA-CRP-XG |
| $^{55}$ $_{26}$Fe | ( 1.0027 ± 0.0023 ) x 10$^3$ d | EC | 1.0 | IAEA-CRP-XG |
| $^{59}$ $_{26}$Fe | 44.494 ± 0.013 d | β$^−$ | 1.0 | IAEA-CRP-XG |
| $^{57}$ $_{27}$Co | 271.8 ± 0.05 d | EC | 1.0 | IAEA-CRP-XG |
| $^{58}$ $_{27}$Co | 70.86 ± 0.06 d | β$^+$ | 0.15 ± 0.0020a | IAEA-CRP-XG | [1] |
| $^{58}$ $_{27}$Co | 70.86 ± 0.06 d | EC | 0.85 ± 0.0020a | IAEA-CRP-XG | [1] |
| $^{60}$ $_{27}$Co | ( 1.92523 ± 0.00027 ) x 10$^3$ d | β$^−$ | 1.0 | IAEA-CRP-XG |
| $^{59}$ $_{28}$Ni | ( 7.6 ± 0.5 ) x 10$^4$ y | EC | 1.0 | ENSDF |
| $^{63}$ $_{28}$Ni | 98.7 ± 2.4 y | β$^−$ | 1.0 | LNHB |
| $^{65}$ $_{28}$Ni | 2.51719 ± 0.00026 h | β$^−$ | 1.0 | ENSDF |
| $^{64}$ $_{29}$Cu | 0.52929 ± 0.00018 d | β$^+$ | 0.179 ± 0.002a | IAEA-CRP-XG | [1] |
| $^{64}$ $_{29}$Cu | 0.52929 ± 0.00018 d | β$^−$ | 0.39 ± 0.003a | IAEA-CRP-XG | [1] |
| $^{64}$ $_{29}$Cu | 0.52929 ± 0.00018 d | EC | 0.431 ± 0.005a | IAEA-CRP-XG | [1] |
| $^{66}$ $_{29}$Cu | 5.12 ± 0.014 m | β$^−$ | 1.0 | ENSDF |
| $^{65}$ $_{30}$Zn | 243.86 ± 0.2 d | β$^+$ | 0.0142 ± 0.0001a | IAEA-CRP-XG | [1] |
| $^{65}$ $_{30}$Zn | 243.86 ± 0.2 d | EC | 0.9858 ± 0.0001a | IAEA-CRP-XG | [1] |
| $^{93m}$ $_{41}$Nb | ( 5.73 ± 0.22 ) x 10$^3$ d | IT | 1.0 | IAEA-CRP-XG |
| $^{93}$ $_{42}$Mo | ( 4.0 ± 0.8 ) x 10$^3$ y | EC | 1.0 | ENSDF |
| $^{99m}$ $_{43}$Tc | 0.250281 ± 0.000022 d | β$^−$ | 0.000037 ± 0.000006a | IAEA-CRP-XG | [1] |
| $^{99m}$ $_{43}$Tc | 0.250281 ± 0.000022 d | IT | 0.999963 ± 0.000006a | IAEA-CRP-XG | [1] |
| $^{110m}$ $_{47}$Ag | 249.85 ± 0.1 d | IT | 0.0136 ± 0.0008a | IAEA-CRP-XG | [1] |
| $^{110m}$ $_{47}$Ag | 249.85 ± 0.1 d | β$^−$ | 0.9864 ± 0.0008a | IAEA-CRP-XG | [1] |
| $^{115m}$ $_{49}$In | 4.486 ± 0.004 h | β$^−$ | 0.05 ± 0.008 | ENSDF |
| $^{115m}$ $_{49}$In | 4.486 ± 0.004 h | IT | 0.95 ± 0.008 | ENSDF |
| $^{126}$ $_{53}$I | 12.93 ± 0.05 d | β$^−$ | 0.473 ± 0.006 | ENSDF |
| $^{126}$ $_{53}$I | 12.93 ± 0.05 d | EC | 0.527 ± 0.006 | ENSDF |
| $^{175}$ $_{72}$Hf | 70 ± 2 d | EC | 1.0 | ENSDF |
| $^{181}$ $_{72}$Hf | 42.39 ± 0.06 d | β$^−$ | 1.0 | ENSDF |
| $^{182}$ $_{73}$Ta | 114.43 ± 0.04 d | β$^−$ | 1.0 | ENSDF |
| $^{181}$ $_{74}$W | 121.2 ± 0.2 d | EC | 1.0 | ENSDF |
| $^{185}$ $_{74}$W | 75.1 ± 0.3 d | β$^−$ | 1.0 | ENSDF |
| $^{187}$ $_{74}$W | 23.72 ± 0.06 h | β$^−$ | 1.0 | ENSDF |
| $^{198}$ $_{79}$Au | 2.695 ± 0.0007 d | β$^−$ | 1.0 | IAEA-CRP-XG |
| $^{197}$ $_{80}$Hg | 64.14 ± 0.05 h | EC | 1.0 | ENSDF |
| $^{203}$ $_{80}$Hg | 46.594 ± 0.012 d | β$^−$ | 1.0 | IAEA-CRP-XG |
| LNHB | Laboratoire National Henri Becquerel, Recommended Data, http://www.nucleide.org/DDEP_WG/DDEPdata.htm Archived 2021-02-13 at the Wayback Machine, 5 June 2008. |
| IAEA-CRP-XG | M.-M. Bé, V.P. Chechev, R. Dersch, O.A.M. Helene, R.G. Helmer, M. Herman, S. Hlav ác, A. Marcinkowski, G.L. Molnár, A.L. Nichols, E. Schönfeld, V.R. Vanin, M.J. Woods, IAEA CRP "Update of X Ray and Gamma Ray Decay Data Standards for Detector Calibration and Other Applications", IAEA Scientific and Technical Information report STI/PUB/1287, May 2007, International Atomic Energy Agency, Vienna, Austria, ISBN 92-0-113606-4. |
| ENSDF | Evaluated Nuclear Structure Data File, http://www-nds.iaea.org/ensdf/, 5 June 2008. |
[1] Branching fractions from LNHB database.
[2] Branching fractions renormalised to sum to 1.0..