Isomeric yield ratio of 196m, gAu in the 197Au(n, 2n) reaction with fast neutron based on the 9Be(p, n) reaction

Abstract

Abstract.The isomeric yield ratios (IR) of 196m, gAu in the 197Au(n, 2n) reaction at the average neutron energies ($ \\langle E_{n}\\rangle$〈En〉) of 14.4, 21.8 and 29.5 MeV have been measured by using the off-line gamma-ray spectrometric technique. The neutron beams were obtained by using the 9Be(p, n) reaction with the proton energies of 25, 35 and 45 MeV from the MC-50 cyclotron at KIRAMS. The IR values at different neutron energies were also calculated from the cross sections values based on TENDL-2017 library and are found to be in agreement around 10–18 MeV but not at higher energy. The IR values of 196m, gAu at the neutron energies of 21.8 and 29.5 MeV have been measured for the first time. The present data along with the literature data at other energies in the 197Au(n, 2n) reaction are compared with the similar data in the 197Au($ \\gamma$γ, n) reaction to examine the role of entrance channel parameters and occurrence of non-compound or pre-equilibrium process at higher projectile energy.