Production and decay of excited quasiprojectiles in peripheral and semiperipheral 35 Cl + 197 Au reactions in Fermi energy domain

The peripheral and semiperipheral reactions in ${}^{35}\mathrm{Cl}{+}^{197}\mathrm{Au}$ have been studied at 30 and 43 MeV/nucleon. The nonequilibrium $\ensuremath{\alpha}$ and IMF components have been observed in the experiment. The fraction of nonequilibrium emission decreases with an increase in the atomic number of the projectilelike fragments but, for a given projectilelike fragment, it increases with the charge of the emitted particles. The characteristics of quasiprojectiles reconstructed from their decay products reveal several features reminiscent of damped reactions at lower bombarding energies. The atomic number and deflection angle of projectilelike fragments depend strongly on their kinetic energy or dissipated energy. At 30 MeV/nucleon, the experimental data can be explained by a deep inelastic transfer model. One-body dissipation is still the main mechanism for the energy and angular momentum dissipation. However, at 43 MeV/nucleon, deep inelastic transfer models can predict only the experimental tendency. Two-body dissipation plays a more important role at higher incident energies. The similarity observed in the decay product distributions, as a function of excitation energy, suggests that the excited quasiprojectiles formed in binary collisions might approach thermal equilibrium for both incident energies. The decay products have been analyzed with sequential-binary and simultaneous-disassembly statistical decay models. Both statistical models are able to provide good agreement with the experimental observables except for the mean kinetic energy of the products.