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[1]
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 106 y β 1.0 ENSDF
14
6
C
( 5.7 ± 0.03 ) x 103 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]
β+ 0.8989 ± 0.0002a
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 105 y EC 0.1825 ± 0.0023b LNHB [2]
β+ 0.8175 ± 0.0023b
35
16
S
87.32 ± 0.16 d β 1.0 LNHB
36
17
Cl
( 0.01 ± 0.03 ) x 105 y EC 0.019 ± 0.001 LNHB
β 0.981 ± 0.001
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 1011 d EC 0.1086 ± 0.0013a IAEA-CRP-XG [1]
β 0.8914 ± 0.0013a
42
19
K
12.36 ± 0.012 h β 1.0 ENSDF
41
20
Ca
( 1.02 ± 0.07 ) x 105 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 103 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]
EC 0.85 ± 0.0020a
60
27
Co
( 1.92523 ± 0.00027 ) x 103 d β 1.0 IAEA-CRP-XG
59
28
Ni
( 7.6 ± 0.5 ) x 104 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]
β 0.39 ± 0.003a
EC 0.431 ± 0.005a
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]
EC 0.9858 ± 0.0001a
93m
41
Nb
( 5.73 ± 0.22 ) x 103 d IT 1.0 IAEA-CRP-XG
93
42
Mo
( 4.0 ± 0.8 ) x 103 y EC 1.0 ENSDF
99m
43
Tc
0.250281 ± 0.000022 d β 0.000037 ± 0.000006a IAEA-CRP-XG [1]
IT 0.999963 ± 0.000006a
110m
47
Ag
249.85 ± 0.1 d IT 0.0136 ± 0.0008a IAEA-CRP-XG [1]
β 0.9864 ± 0.0008a
115m
49
In
4.486 ± 0.004 h β 0.05 ± 0.008 ENSDF
IT 0.95 ± 0.008
126
53
I
12.93 ± 0.05 d β 0.473 ± 0.006 ENSDF
EC 0.527 ± 0.006
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..


References

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  1. ^ "Half-lives and decay branching fractions for activation products". www-nds.iaea.org. IAEA. Retrieved 11 November 2016.
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