Monte Carlo calculation of prompt-fission observables within the Langevin dynamics and the Weisskopf statistical model

In this work, the Langevin approach within the two-center shell model incorporated with the statistical evaporation model is applied to consistently describe the fission dynamics and the deexcitation process of primary fragments. The charge distribution and the ratio of the average neutron number to proton number of fission fragments, the preneutron and postneutron mass distributions, the total kinetic energy (TKE) distribution and the TKE-mass correlation of fragments, as well as the multiplicity and energy spectrum of prompt neutron in $^{235}\mathrm{U}$ fission induced by thermal and 14 MeV neutron are calculated with the present approach. The calculation results are overall in good agreement with available experimental data and GEF calculations. In addition, the excitation energy distribution of the fission fragments and the correlation between the neutron multiplicity and the TKE are studied within the present model and are highly reasonable. It is straightforward to extend the present approach to study the fission observables for high-energy neutron induced fission on actinides, where multichance fission plays a more important role.