Investigation of role of entrance channel mass asymmetry on fusion fission dynamics

The fusion-fission dynamic process has been stimulating the interests of nuclear physicists from several years and still understanding the dynamics of fusion-fission process is an active field of research. A number of attempts have been made in the past few decades to estimate the strength of nuclear dissipation in fusion-fission dynamics. Various probes are used to carry out these measurements such as neutron multiplicity, charged particles multiplicity, evaporation residue cross-section etc. In the present work the effect of entrance channel has been studied in reactions 12C + 204Pb and 19F + 197Au populating same compound nucleus 216Ra using statistical model (SM) VECSTAT by simultaneously explaining both neutron multiplicities and fission\evaporation residue cross-sections by separately taking in account the reduced dissipation coefficient sensitive from equilibrium to saddle (βgs) and saddle to scission (βss) regime. The work shows that smaller βgs values are required to explain fission\evaporation residue (ER) cross-sections and larger βss values are required to explain neutron multiplicities and for consistent SM analysis fission\evaporation residue cross-sections are more appropriate tools to investigate entrance channel effects rather than neutron multiplicities.