Fission cross-section measurement for 238U(n,f)134 ZX reactions induced by D-T neutrons

Abstract

The D-T neutron induced fission fragments from 238U, i.e., 134Te, 134 mI and 134 gI, were measured by low-background HPGe-γ detector. The fission cross-sections of the 238U(n, f) 134Te, 238U(n, f))134 mI and 238U(n, f)134 gI reactions induced by D-T neutrons, i.e., 14.7 ± 0.3, 14.5 ± 0.3 and 14.1 ± 0.3 MeV, were measured precisely with the neutron activation technique, where the neutron flux was monitored by accompanying α-particle and the neutron energy was determined by the cross-section ratio of 90Zr(n, 2 n)89Zr to 93Nb(n, 2 n)92 mNb reaction. The fission cross-sections of the 238U(n, f)134Te reaction are 54.3 ± 3.5 mb, 52.6 ± 3.4 mb and 50.0 ± 3.2 mb, corresponding to the above energy points. However, the cross-sections of 238U(n, f)134 gI reactions were estimated to be below a value about 8.2 × 10−3 mb, since almost all the 134 gI nuclide, of which characteristic γ-rays were detected in the spectrum, originated from the 134Te decay. Meanwhile, the characteristic γ-rays of 134 mI were not found on any spectrum, and beyond the lower limit of measurement.