Angular distribution of fragments in neutron-induced nuclear fission at energies 1-200 MeV: data, theoretical models and relevant problems

Abstract

In recent years, investigations of angular distributions of fragments in neutron-induced nuclear fission have been extended to intermediate energies, up to 200 MeV, as well as to a wide range of target isotopes. Using as an example the latest data obtained by our group for the reaction 237-Np(n,f), we discuss the specific features of fission fragment angular distribution and present a method for their simulation based on the code TALYS. It is shown that a simplified model reasonably describes energy dependence of the angular distribution in the whole range 1-200 MeV. The ways to improve the model are discussed along with the possibilities to use it for obtaining new information on fission and pre-equilibrium processes in neutron-nucleus interaction. We consider also the relevant problems of describing fission fragment angular distributions.

Comments: 11 pages, 3 figures, Research was presented at the THEORY-5 Scientific Workshop on "Nuclear Fission Dynamics and the Emission of Prompt Neutrons and Gamma Rays", Castelvecchio Pascoli, Barga, Italy, September 24-26, 2019