Nuclear geometry and nuclear fragments in relativistic nucleus-nucleus collisions

Abstract

The nuclear geometry including the volumes and surface areas of the participant and the spectator in relativistic nucleus-nucleus collisions are calculated. The analyses of the transverse energy distributions show that the calculated results by using the nuclear geometry picture are in good agreement with the experimental data. There is no obvious difference between the Woods-Saxon shape and the even one of nucleon number density distribution in studying the transverse energy distribution. The charge and multiplicity distributions of projectile fragments produced in relativistic nucleus-nucleus collisions have been analysed by a two-source emission picture. A Monte Carlo partition method is used to simulate the production of projectile fragments in nuclear diffractive excitation and electromagnetic dissociation. We have studied the charge distributions of projectile fragments in the case of including and excluding the heaviest fragment, the charge distribution of the heaviest fragment, the multiplicity distributions of projectile H and He fragments and all fragments excluding the heaviest one, as well as the correlation between the heaviest fragment charge and fragments multiplicity. The calculated results are in agreement with the experimental data of sulphur fragmentation at the highest energy per nucleon in the present accelerator energy region.