High-Spin Studies of Fission Products in Fusion-Evaporation Reactions

High-spin states of several isotopes in the mass A ∼ 100 region have been investigated following the fission of compound nuclei formed in three heavy-ion fusion-evaporation reactions. New sequences have been assigned to ⁹¹Sr, ¹⁰⁷Ru, and ^{113,115,117,119}Cd isotopes using the complementary fission fragment technique. The ground-state bands have been extended to higher spins in ^{114,116,118,120}Cd. The level schemes of ^88,90,92Sr and ¹⁰¹Tc 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. The prompt γ-ray intensity distributions of the fragments following the fission of the ¹⁹⁷Pb compound nucleus are reported. The empirical distributions as a function of Z and A are not reproduced by expected yields of symmetric fission. Rather these distributions reflect the selectivity of Gammasphere to detect collective nuclei and to study high-spin excitations in fission fragments.