Production of evaporation residues in the O16+Pb208 and Ca48+Yb176 reactions

Abstract

Cross section data for evaporation residues (ERs) produced in the $^{16}\mathrm{O}+^{208}\mathrm{Pb}$ and $^{48}\mathrm{Ca}+^{176}\mathrm{Yb}$ heavy-ion fusion-evaporation reactions leading to the same $^{224}\mathrm{Th}^{*}$ compound nucleus (CN) were obtained at energies around the fusion reaction barriers with the recoil separator vassilissa. These data for ERs formed in the most probable evaporation channels in both reactions agree with those obtained earlier. ER and fission cross sections for $^{16}\mathrm{O}+^{208}\mathrm{Pb}$ are well reproduced with model calculations using adjustment of respective model parameters. The mutual comparison of the ER cross sections for the very asymmetric ($^{16}\mathrm{O}+^{208}\mathrm{Pb}$) and more symmetric ($^{48}\mathrm{Ca}+^{176}\mathrm{Yb}$) projectile-target combinations allowed us to obtain the fusion probability value (CN formation probability) imposed by the quasifission effect inherent in the $^{48}\mathrm{Ca}+^{176}\mathrm{Yb}$ reaction.