Excitation and multiple dissociation of projectiles at intermediate energy

Cross sections for the multiple breakup of 16O, 14N and 12C projectiles scattered by a Au target were measured with an array of 34 phoswich detectors. The dissociation of the projectiles into as many as five charged particles has been observed. The yields of different exit channels correlate approximately with the threshold energy for separation of the projectile into the observed fragments. The excitation spectrum of the primary projectile-like nucleus was reconstructed from the measured positions and kinetic energies of the individual fragments. The energy sharing between projectile and target is consistent with a fast excitation mechanism in which differential increases in projectile excitation energy appear to be accompanied by comparable increases in target excitation. Calculations of the yields based on a sequence of binary decays are presented. The question of prompt or sequential decay is also considered by examining the directional correlations of the particles. 19 refs., 8 figs