Simulation technique for the measurement of fast neutron reaction cross sections

Abstract

There is a need for precision measurement of the fast neutron cross sections, wherever they are, a few tens of millibarns or less in magnitude. In these cases, since large samples and large solid angles have to be used to get good statistics, complex corrections have to be applied for self-scattering and self-absorption effects in the target and pile-up effects in the detector. We have measured fast neutron cross sections for 58Ni(n, 2n)57Ni, 75As(n, α)72Ga, 138Ba(n, p)138Cs and 138Ba(n, α)135m, gXe reactions usi powder technique together with a high resolution (1.78 keV fwhm for 1.33 MeV photons) HPGe detector. Special care is taken to determine the above corrections experimentally by a "simulation technique", which enables the exact magnitude of corrections to be known precisely. © 1986.