High-spin studies of fission products in fusion-evaporation reactions

High-spin states of several isotopes in the mass A similar to 100 region ha ve been investigated following the fission of compound nuclei formed in thr ee heavy-ion fusion-evaporation reactions. New sequences have been assigned to Sr-91, Ru-107 and Cd-113,Cd-115,Cd-117,Cd-119 isotopes using the comple mentary fission fragment technique. The ground-state bands have been extend ed to higher spins in Cd-114,Cd-116,Cd-118,Cd-120. The level schemes of Sr- 88,Sr-90,Sr-92 and Tc-101 have been considerably enriched. The plethora of results demonstrates the efficiency in which spectroscopic information can be collected on nuclei near the line of stability or slightly neutron-rich from studies of fission fragments following fusion-evaporation reactions. T he prompt gamma-ray intensity distributions of the fragments following the fission of the Pb-197 compound nucleus are reported. The empirical distribu tions as a function of Z and A are not reproduced by expected yields of sym metric fission. Rather these distributions reflect the selectivity of Gamma sphere to detect collective nuclei and to study high-spin excitations in fi ssion fragments.