Excitation energy and angular momentum of quasiprojectiles produced in the Xe plus Sn collisions at incident energies between 25 and 50 MeVucleon

摘要

The excitation energy and angular momentum transferred to quasiprojectiles have been measured in the Xe-129 + Sn-nat collisions at bombarding energies between 25 and 50 MeVucleon. The excitation energy of quasiprojectiles has been determined from the kinetic energy of all decay products (calorimetry). It increases with the violence of the collision, approaching 10 MeVucleon in the most dissipative ones. The angular momentum has been deduced from the kinetic energies and angular distributions of the emitted light charged particles (p, d, t, He-3 and alpha). The (apparent) spin value decreases with the violence of the collision. Larger spin values are observed at the lowest bombarding energy. Data are compared with the predictions of dynamical and statistical models. They reproduce the data in a quantitative way indicating that large spin values are transferred to quasiprojectiles during the interaction. The results show that the one-body dissipation formalism still applies at intermediate bombarding energies and low-energy dissipations. With the increase of the energy, the data seem to be better described when the two-body interaction is accounted for. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 65]