NUCLEAR TEMPERATURE OF THE DISASSEMBLING SOURCE IN CENTRAL HEAVY-ION COLLISIONS FROM ISOTOPE YIELDS

We modify the method of Albergo et al. for determining the temperature of an excited nucleus from double ratios of isotope yields and presen t a statistical model which accounts for the population and decay of e xcited states of the emitted fragments. Nuclear temperatures are extra cted using experimental ratios of isotopic yields of fragments from he lium through carbon for the reactions Ca-40 + Ni-58, Ar-40 + Ni-58, Ca -40 + Fe-58, and Ar-40 + Fe-58 at 33 MeV/nucleon projectile energy. Us ing the model we obtain consistent values for the temperature from Var ious isotope combinations within the experimental error when accountin g for the population and decay of the excited fragments.