High-Spin States of 84,85Br: Mapping the Proton Sub-Shells towards 78Ni

摘要

The 84,85Br nuclei have been produced as fission fragments in the fusion reaction 18O+208Pb at 85 MeV bombarding energy and studied with the Euroball IV array. The high-spin states of the odd-odd 84Br nucleus have been identified for the first time. From angular correlation analysis, spin values have been assigned to most of the 85Br excited states up to 4 MeV. All observed states in 84,85Br can be described by various proton excitations involving at least the two sub-shells (f5/2 and p3/2) located just above the Z = 28 shell closure.