Book Description

Dynamical and statistical aspects of heavy ion collisions were studied. These investigations concerned themselves mainly with the study of collisions between very heavy ions where there is little or no fusion. For these reactions the reaction cross section is exhausted by the strongly damped processes. However, also some models for collision between light ions, where fusion plays an important role were investigated. The dynamics was improved by introducing collective degrees of freedom which absorb energy from the relative motion. Two models which account for the effect of collective deformation are studied. The first is phenomenological, according to which the effect of deformations is reproduced by having different potentials in the entrance and exit channels. According to the second collective degrees are taken into account explicitly and included in the Lagrangian formalism. Three collective degrees of freedom are used: necking, stretching, and mass asymmetry. The dependence of the inertias, potentials and friction on these degrees of freedom and the corresponding velocities, are calculated from first principles. Finally transfer, which plays an essential role in strongly damped collision, is introduced into the model. Transfer affects the dynamics and the other way around. This feedback effect is demonstrated. Transfer is considered as a random process according to the present model. A list of publications is included.