Variation of total kinetic energy and mass distributions in the fusion-fission reaction of 16O,19F + 209Bi at near barrier energies

Abstract

Fission fragment mass and energy distributions and their correlations have been measured for the 16O and 19F + 209Bi reactions over a wide range of excitation energies ( E * = 30-50 MeV). It is observed that in the case of 16O + 209Bi reaction, the average total fragment kinetic energy, is nearly independent of the bombarding energy. However, in the case of 19F + 209Bi reaction, the average total kinetic energy of the fission fragments shows a peaking behaviour near the barrier. The variation in at near barrier energies in the 19F + 209Bi system seems to be correlated with corresponding strong variation in the variance of the fragment mass distribution. The present results may imply certain dynamical effects leading to compact scission configurations in the fission of 19F + 209Bi system at near barrier bombarding energies.