Spectrum-Averaged Cross Section Measurements of 75As(n,2n)74As, 75As(n,α)72Ga, and 74Se(n,p)74As Using 252Cf Neutron Source

Abstract The validation of cross sections is crucial for achieving satisfactory reliability in calculations. Spectrum-averaged cross sections (SACSs) in a 252Cf(s.f.) standard neutron field are a preferred tool for cross section validation. This study focuses on validating the cross sections of the 75As(n,2n)74As, 75As(n,α)72Ga, and 74Se(n,p)74As reactions. Spectrum-averaged cross sections were derived from the measured activities of irradiated samples by means of gamma spectroscopy. The experimental data were compared with mcnp6.3 calculations using cross sections from jeff-3.3, endf/b-viii.1, or jendl-5 libraries. Good agreement of experimental SACS with calculational one was observed for the 75As(n,2n)74As reaction in all mentioned libraries. However, a disagreement was identified for the 75As(n,α)72Ga reaction. Moreover, the calculations for the 74Se(n,p)74As reaction yielded very unsatisfactory results. The cross sections of the 75As(n,α)72Ga and 74Se(n,p)74As reactions require reevaluation, and further experiments are necessary. The experimentally estimated spectrum-averaged cross sections in a 252Cf(s.f.) neutron field of 75As(n,2n)74As, 75As(n,α)72Ga, and 74Se(n,p)74As reactions were as follows: 0.623 ± 0.022 mb, 0.0316 ± 0.0022 mb, and 1.34 ± 0.07 mb. These measurements represent the first reported SACS values for these reactions in the 252Cf(s.f.) neutron field.