Finite-size effects on fragmentation in heavy-ion collisions

Abstract

To investigate the influence of nuclear finite-size effects on the fragmentation in heavy-ion collisions, the fragment charge distributions of ${}^{40}$Ca+${}^{40}$Ca, ${}^{197}$Au+${}^{197}$Au, ${}^{120}$Xe+${}^{129}$Sn, and ${}^{58}$Ni+${}^{48}$Ca at intermediate incident energies are studied by using the improved quantum molecular dynamics model. Both the width of the wave packet at the coordinate space and the surface energy term strongly affect the formation and stability of fragments at intermediate-low energies. The wave-packet width influences the stability and the central densities of the initial nuclei. With increase of incident energies, the influence of the detail in description of individual nucleons and of their interaction via mean field on the fragment distributions weakens gradually.