An exclusive analysis of dissipation for light heavy-ion collisions at intermediate energy within the hybrid model

Abstract

The reverse kinematics light heavy-ion system 35Cl+ 12C at 43 MeV/nucleon is investigated in the framework of a dynamical-statistical hybrid model. The modified quantum molecular dynamics model which includes a Pauli potential is used to describe the initial non-equilibrium stage of the reaction and the formation of highly excited pre-fragments. The decay of pre-fragments is further described with a statistical sequential decay code. The distributions of global observables from filtered simulations, such as the center-of-mass velocity of products, fragment charge, anisotropy ratio and flow angle, reproduce the experimental results remarkably well. The evolutions between the number of sources and flow angle with impact parameter are investigated and compared with experimental results. For the light heavy-ion system, binary dissipative collision is a dominant reaction process. The process is still present even in central collisions. The formation of a neck-like structure can be observed at mid-central collision in the simulations. From a comparison to Boltzmann-Uehling-Uhlenbeck model calculations, a possible origin of the neck-like structure for the present system could be the mean-field instabilities which originate from dynamical fluctuations through the time evolution of the collision.