Fission dynamics of intermediate-fissility systems: A study within a stochastic three-dimensional approach

The system of intermediate fissility ¹³²Ce has been studied experimentally and theoretically to investigate the dissipation properties of nuclear matter. Cross sections of fusion-fission and evaporation-residue channels together with light charged particle multiplicities in both channels, their spectra, light charged particle-evaporation residue angular correlations, and mass-energy distribution of fission fragments have been measured. Theoretical analysis has been performed using a multidimensional stochastic approach coupled with a Hauser-Feshbach treatment of particle evaporation. The main conclusions are that the full one-body shape-dependent dissipation mechanism allows the reproduction of the full set of experimental data and that after a time τd=5×10^-21 s from the equilibrium configuration of the compound nucleus, fission decay can occur in a time that can span several orders of magnitude.