Analysis of fusion-fission dynamics by pre-scission neutron emission in $^{58}$Ni+$^{208}$Pb

We analyzed the experimental data of the pre-scission neutron multiplicity in con-nection with fission fragments in the reaction 58 Ni+ 208 Pb at the incident energy corresponding to the excitation energy of compound nucleus E ∗ =185.9 MeV, which was performed by D´eMoN group. The relation between the pre-scission neutron multiplicity and each reaction process having different reaction time is investigated. In order to study the fusion-fission process accompanied by neutron emission, the fluctuation-dissipation model combined with a statistical model is employed. It is found that the fusion-fission process and the quasi-fission process are clearly distinguished in correlation with the pre-scission neutron multiplicity.