Activation product explained

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]
NuclideHalf-lifeDecay modebranching fractionSourceNotes
12.312 ± 0.025 yβ1.0LNHB
(1.51 ± 0.06) x 106 yβ1.0ENSDF
(5.7 ± 0.03) x 103 yβ1.0LNHB
2.449 ± 0.005 sβ1.0ENSDF
7.13 ± 0.02 sβ1.0ENSDF
26.88 ± 0.05 sβ1.0ENSDF
950.57 ± 0.23 dEC0.1011 ± 0.0002aIAEA-CRP-XG[1]
β+0.8989 ± 0.0002a
0.62329 ± 0.00006 dβ1.0IAEA-CRP-XG
9.458 ± 0.012 mβ1.0ENSDF
(7.17 ± 0.24) x 105 yEC0.1825 ± 0.0023bLNHB[2]
β+0.8175 ± 0.0023b
87.32 ± 0.16 dβ1.0LNHB
(0.01 ± 0.03) x 105 yEC0.019 ± 0.001LNHB
β0.981 ± 0.001
269 ± 3 yβ1.0ENSDF
109.61 ± 0.04 mβ1.0ENSDF
(4.563 ± 0.013) x 1011 dEC0.1086 ± 0.0013aIAEA-CRP-XG[1]
β0.8914 ± 0.0013a
12.36 ± 0.012 hβ1.0ENSDF
(1.02 ± 0.07) x 105 yEC1.0ENSDF
162.61 ± 0.09 dβ1.0ENSDF
3.3492 ± 0.0006 dβ1.0ENSDF
43.67 ± 0.09 hβ1.0ENSDF
27.7009 ± 0.002 dEC1.0IAEA-CRP-XG
312.29 ± 0.26 dEC1.0IAEA-CRP-XG
0.107449 ± 0.000019 dβ1.0IAEA-CRP-XG
(1.0027 ± 0.0023) x 103 dEC1.0IAEA-CRP-XG
44.494 ± 0.013 dβ1.0IAEA-CRP-XG
271.8 ± 0.05 dEC1.0IAEA-CRP-XG
70.86 ± 0.06 dβ+0.15 ± 0.0020aIAEA-CRP-XG[1]
EC0.85 ± 0.0020a
(1.92523 ± 0.00027) x 103 dβ1.0IAEA-CRP-XG
(7.6 ± 0.5) x 104 yEC1.0ENSDF
98.7 ± 2.4 yβ1.0LNHB
2.51719 ± 0.00026 hβ1.0ENSDF
0.52929 ± 0.00018 dβ+0.179 ± 0.002aIAEA-CRP-XG[1]
β0.39 ± 0.003a
EC0.431 ± 0.005a
5.12 ± 0.014 mβ1.0ENSDF
243.86 ± 0.2 dβ+0.0142 ± 0.0001aIAEA-CRP-XG[1]
EC0.9858 ± 0.0001a
(5.73 ± 0.22) x 103 dIT1.0IAEA-CRP-XG
(4.0 ± 0.8) x 103 yEC1.0ENSDF
0.250281 ± 0.000022 dβ0.000037 ± 0.000006aIAEA-CRP-XG[1]
IT0.999963 ± 0.000006a
249.85 ± 0.1 dIT0.0136 ± 0.0008aIAEA-CRP-XG[1]
β0.9864 ± 0.0008a
4.486 ± 0.004 hβ0.05 ± 0.008ENSDF
IT0.95 ± 0.008
12.93 ± 0.05 dβ0.473 ± 0.006ENSDF
EC0.527 ± 0.006
70 ± 2 dEC1.0ENSDF
42.39 ± 0.06 dβ1.0ENSDF
114.43 ± 0.04 dβ1.0ENSDF
121.2 ± 0.2 dEC1.0ENSDF
75.1 ± 0.3 dβ1.0ENSDF
23.72 ± 0.06 hβ1.0ENSDF
2.695 ± 0.0007 dβ1.0IAEA-CRP-XG
64.14 ± 0.05 hEC1.0ENSDF
46.594 ± 0.012 dβ1.0IAEA-CRP-XG
LNHB Laboratoire National Henri Becquerel, Recommended Data, http://www.nucleide.org/DDEP_WG/DDEPdata.htm, 5 June 2008.
IAEA-CRP-XGM.-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, .
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

Notes and References

  1. Web site: Half-lives and decay branching fractions for activation products. www-nds.iaea.org. IAEA. 11 November 2016.