LIGHT CHARGED-PARTICLE AND INTERMEDIATE-MASS FRAGMENT EMISSION IN THEREACTION 640 MEV KR-86-63(CU)

Light-charged particles from the reaction 640 MeV Kr-86 + Cu-63 have b een measured in singles and in coincidence with intermediate mass frag ments, fissionlike fragments, and other light-charged particles. Multi plicities for H-1 and He-4 in association with the evaporation residue s, fragments, and intermediate mass fragments have been determined. Co mposite nuclei, most of which decay to evaporation residues, are the m ajor sources of evaporative light-charged particle emission. Average m ultiplicities for prescission H-1 and He-4 can be associated with the composite nucleus en route to scission; they are relatively large and thus suggest a time scale for fission longer than that for evaporation . The multiplicities for H-1 and He-4 in association with the intermed iate mass fragments indicate that these fragments are usually born wit h a significant quantity of excitation energy. These multiplicities ar e used to estimate the primary masses and kinetic energies of the inte rmediate mass fragments.