Trends in fragment heating in the damped reaction ¹⁶⁵Ho+⁵⁶Fe at 7.2 MeV/nucleon

Neutron folds in two high-efficiency neutron multiplicity meters (NMM) were measured in coincidence with projectilelike fragments from the ¹⁶⁵Ho+⁵⁶Fe reaction at a low bombarding energy of E_lab=7.2 MeV/nucleon. Utilizing a complex Monte Carlo procedure to simulate both the fragment decay cascades and the response of the NMM’s, the average excitation energies of the fragments were deduced as functions of the total-kinetic-energy loss. The rather slow evolution of the experimental excitation energy partition from an equipartition at the initial stages of the collision towards its thermal equilibrium limit is found to be in quantitative agreement with the predictions of the one-body nucleon-exchange model.