TALYS calculations of prompt fission observables and independent fission product yields for the neutron-induced fission of ^{235}U

Abstract

The TALYS nuclear reaction code’s Hauser-Feshbach statistical decay model has been adapted in order to calculate prompt fission neutron and gamma -ray observables by iterating over deexciting fission fragments. Several fission fragment generators such as GEF, HF^{3}D, and SPY were employed to provide TALYS with databases. These databases contain standardized tables with fission fragment yields, mean excitation energies and their widths, and average total kinetic energy, as a function of charge and mass number of primary fission fragments. The resulting calculations, including prompt particle multiplicities, spectra, average energies, and independent fission product yields, were compared with experimental and evaluated data. This work first outlines the new methodology implemented in TALYS and examines the effects of three important parameters on the final evaporation data. Furthermore, the neutron-induced fission of ^{235}U is investigated in detail as a function of incident energy. The results from TALYS, with input from GEF and HF^{3}D, were compared with available experimental data and the results of the stand-alone GEF code. The proposed methodology contributes to an improved capability to model the fission process.