Measurement of inclusive photonuclear (γ,n) reaction cross section for 129IAbul Kalam Md. Lutfor Rahman1, Shigeyuki Kuwabara1, Kunio Kato1, Hidehiko Arima1, Nobuhiro Shigyo1, Kenji Ishibashi1, Jun-ichi Hori2, Ken Nakajima2, Tetsuo Goto3 and Mikio Uematsu3
1 Kyushu University, Fukuoka 813-0395, Japan
2 Kyoto University Research Reactor Institute, Osaka 590-0494, Japan
3 Toshiba Corporation, Yokohama 235-8523, Japan
Published online: 21 May 2008
Long-life non-γ emitting radioactive wastes such as 129I and 14C are produced from nuclear waste facilities. The photonuclear reaction is supposed to be usable for measuring the quantity of such nuclides without destruction of waste drum. Photonuclear products of 128I and 13C emit gamma rays and their radiation can be easily detected by a Ge detector. In this study, the inclusive photonuclear reaction cross section of 129I(γ,n) 128I was measured by the use of bremsstrahlung photons from 30-MeV electron LINAC. The amount of produced 128I was measured with an HPGe gamma-ray spectrometer. Experiments were analyzed for both (γ,n) and accompanying (n,γ) reactions. Flux calculations were performed by EGS and MCNP codes. The measured average activation cross section of 129I(γ,n) 128I is 0.096 ± 0.005 barn on the basis of 197Au(γ,n) reaction value. The measured value agrees with the evaluated (IAEA photonuclear data library) cross section within a deviation of 17%. The cross section is usable for non-destructive measurement of the amount of 129I in radioactive waste.
© CEA 2008