The influence of the entrance channel dynamics on the evaporation residue formation

Abstract

The dynamical effects of the entrance channel on the competition between quasifission and fusion processes, and on the evaporation residue formation are investigated. We have analyzed the results and compared our calculations with the experimental data obtained in the 16 O + 204 Pb and 96 Zr + 124 Sn reactions having very different mass asymmetries and leading to the 220 Th * compound nucleus. We have found that different partial capture cross-sections $\sigma_\ell^{\rm cap}(E)$ for these reactions lead to different fusion-quasifission competitions and, consequently, to different partial fusion cross-sections $\sigma_\ell^{\rm fus}(E)$ of the compound nucleus formed in the two reactions. The dynamical conditions also affect the fission-evaporation competition of the excited intermediate nuclei along the CN de-excitation cascade and, consequently, the evaporation residue formation.