Evaluation of neutron nuclear data on mercury isotopes

Shibata, Keiichi

Neutron nuclear data on mercury isotopes have been evaluated for the next version of Japanese Evaluated Nuclear Data Library general-purpose file in the energy region from eV to 20 MeV. Resolved resonance parameters of Hg were supplemented with the data which had not been considered in the previous library. Unresolved resonance parameters were obtained by fitting to the total and capture cross sections calculated from nuclear models. A statistical model code CCONE was applied to evaluate cross sections above the resolved resonance region. Compound, pre-equilibrium and direct-reaction processes were considered for cross-section calculation. Coupled-channel optical model parameters were employed for the interaction between neutrons and mercury isotopes except Hg. The present results reproduce experimental data very well, and are much better than the JENDL-4.0 evaluation. The evaluated data are compiled into ENDF-formatted data files.