Effects of Excitation in Neutron Induced Fissile Isotopes of Uranium Using the OPTMAN Code Up to 20 MeV.

Abstract

In this work, the effects of neutron-induced fissile isotopes of Uranium, particularly; Uranium-233 and Uranium-235 are studied using the Coupled-Channelled Optical Model code (OPMAN) code up to 20 MeV. The high demand for nuclear reactor fuels has necessitated this research. As one of the major naturally occurring radionuclides with lots of fuel prospect, Uranium-233 occurred in trace while Uranium-235 occur in 0.71%. Two steps process away from Uranium-233 and Uranium-235 on neutron capture can produce fissile materials to be used as reactor fuel. Though, Uranium-233 and Uranium-235 are not by them self a fissile material, but, they are breeder reactor fuels. Computations were done for both the Potential Expanded by Derivatives (PED) which account for the Rigid-Rotor Model (RRM) that treat nuclei as rigid vibrating sphere as well as account for nuclear volume conservation and Rotational Model Potentials (RMP) which account for the Soft-Rotator Model (SRM) that treat nuclei as soft rotating spherical deformed shapes. Each of the calculated data was compared with the retrieved data from Evaluated Nuclear Dada File (ENDF) which was found to be in good agreement. The threshold energies in all cases were found to be ≤ 4 MeV for both PED (Potential Expanded by Derivatives) and RMP (Rotational Model Potentials). It is observed that results from RMP much better agreed with the retrieved data than one obtained from PED.

Keywords

• breeder reactor fuel
• optman code
• coupled-channelled optical model
• rigid-rotor model (rrm)
• potential expanded by derivatives (ped)