Isotopic distribution in projectile fragments above the Coulomb barrier

Abstract

We have studied fragmentation properties of projectiles in peripheral heavy-ion collisions within a statisticalensemble approach. Distributions of projectile fragments are calculated for the reaction systems 86 Kr on 58,64 Ni andare compared to the experimental data for the same reactions at projectile energy of 15 MeV/nucleon. We assume thatthe projectile nuclei capture many neutrons from the targets as a result of the multinucleon transfer reactions (directand fast reactions) at the first step of the dynamical stage of the collisions, and then the excited spectators are formedduring the preequilibrium process (multistep reactions) long before the statistical equilibrium stage, and the deexcitationprocesses for the hot sources are simulated within the statistical multifragmentation model. It is seen that predictedresults are in satisfactory agreement with experimental data.