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 1H	12.312 ± 0.025 y	β−	1.0	LNHB
10 4Be	( 1.51 ± 0.06 ) x 106 y	β−	1.0	ENSDF
14 6C	( 5.7 ± 0.03 ) x 103 y	β−	1.0	LNHB
15 6C	2.449 ± 0.005 s	β−	1.0	ENSDF
16 7N	7.13 ± 0.02 s	β−	1.0	ENSDF
19 8O	26.88 ± 0.05 s	β−	1.0	ENSDF
22 11Na	950.57 ± 0.23 d	EC	0.1011 ± 0.0002a	IAEA-CRP-XG	[1]
		β+	0.8989 ± 0.0002a
24 11Na	0.62329 ± 0.00006 d	β−	1.0	IAEA-CRP-XG
27 12Mg	9.458 ± 0.012 m	β−	1.0	ENSDF
26 13Al	( 7.17 ± 0.24 ) x 105 y	EC	0.1825 ± 0.0023b	LNHB	[2]
		β+	0.8175 ± 0.0023b
35 16S	87.32 ± 0.16 d	β−	1.0	LNHB
36 17Cl	( 0.01 ± 0.03 ) x 105 y	EC	0.019 ± 0.001	LNHB
		β−	0.981 ± 0.001
39 18Ar	269 ± 3 y	β−	1.0	ENSDF
41 18Ar	109.61 ± 0.04 m	β−	1.0	ENSDF
40 19K	( 4.563 ± 0.013 ) x 1011 d	EC	0.1086 ± 0.0013a	IAEA-CRP-XG	[1]
		β−	0.8914 ± 0.0013a
42 19K	12.36 ± 0.012 h	β−	1.0	ENSDF
41 20Ca	( 1.02 ± 0.07 ) x 105 y	EC	1.0	ENSDF
45 20Ca	162.61 ± 0.09 d	β−	1.0	ENSDF
47 21Sc	3.3492 ± 0.0006 d	β−	1.0	ENSDF
48 21Sc	43.67 ± 0.09 h	β−	1.0	ENSDF
51 24Cr	27.7009 ± 0.002 d	EC	1.0	IAEA-CRP-XG
54 25Mn	312.29 ± 0.26 d	EC	1.0	IAEA-CRP-XG
56 25Mn	0.107449 ± 0.000019 d	β−	1.0	IAEA-CRP-XG
55 26Fe	( 1.0027 ± 0.0023 ) x 103 d	EC	1.0	IAEA-CRP-XG
59 26Fe	44.494 ± 0.013 d	β−	1.0	IAEA-CRP-XG
57 27Co	271.8 ± 0.05 d	EC	1.0	IAEA-CRP-XG
58 27Co	70.86 ± 0.06 d	β+	0.15 ± 0.0020a	IAEA-CRP-XG	[1]
		EC	0.85 ± 0.0020a
60 27Co	( 1.92523 ± 0.00027 ) x 103 d	β−	1.0	IAEA-CRP-XG
59 28Ni	( 7.6 ± 0.5 ) x 104 y	EC	1.0	ENSDF
63 28Ni	98.7 ± 2.4 y	β−	1.0	LNHB
65 28Ni	2.51719 ± 0.00026 h	β−	1.0	ENSDF
64 29Cu	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 29Cu	5.12 ± 0.014 m	β−	1.0	ENSDF
65 30Zn	243.86 ± 0.2 d	β+	0.0142 ± 0.0001a	IAEA-CRP-XG	[1]
		EC	0.9858 ± 0.0001a
93m 41Nb	( 5.73 ± 0.22 ) x 103 d	IT	1.0	IAEA-CRP-XG
93 42Mo	( 4.0 ± 0.8 ) x 103 y	EC	1.0	ENSDF
99m 43Tc	0.250281 ± 0.000022 d	β−	0.000037 ± 0.000006a	IAEA-CRP-XG	[1]
		IT	0.999963 ± 0.000006a
110m 47Ag	249.85 ± 0.1 d	IT	0.0136 ± 0.0008a	IAEA-CRP-XG	[1]
		β−	0.9864 ± 0.0008a
115m 49In	4.486 ± 0.004 h	β−	0.05 ± 0.008	ENSDF
		IT	0.95 ± 0.008
126 53I	12.93 ± 0.05 d	β−	0.473 ± 0.006	ENSDF
		EC	0.527 ± 0.006
175 72Hf	70 ± 2 d	EC	1.0	ENSDF
181 72Hf	42.39 ± 0.06 d	β−	1.0	ENSDF
182 73Ta	114.43 ± 0.04 d	β−	1.0	ENSDF
181 74W	121.2 ± 0.2 d	EC	1.0	ENSDF
185 74W	75.1 ± 0.3 d	β−	1.0	ENSDF
187 74W	23.72 ± 0.06 h	β−	1.0	ENSDF
198 79Au	2.695 ± 0.0007 d	β−	1.0	IAEA-CRP-XG
197 80Hg	64.14 ± 0.05 h	EC	1.0	ENSDF
203 80Hg	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..

External links

• Handbook on Nuclear Activation Cross-Sections, IAEA, 1974
• Nuclear Structure and Decay Databases (nndc.bnl.gov)
• New and revised half-life measurements results made by the Radioactivity Group of NIST
• HANDBOOK OF NUCLEAR DATA FOR SAFEGUARDS: DATABASE EXTENSIONS, AUGUST 2008