Analysis of fusion-fission dynamics by pre-scission neutron emission in 58Ni+208Pb system

We analyzed the experimental data of the pre-scission neutron multiplicity in connection with fission fragments in the reaction Ni-58 + Pb-208 at the incident energy corresponding to the excitation energy of the compound nucleus E* = 185.9 MeV, which was performed by DeMoN 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. (c) 2005 Elsevier B.V. All rights reserved.