g-ray spectroscopy of core-excited states in 51Mn

The level scheme of 51Mn has been investigated using the 28Sis32S ,2a1pd51Mn fusion-evaporation reaction at 125 MeV beam energy. The g rays were detected in the Ge-detector array Gammasphere, which was coupled to the 4p-charged-particle detector Microball and the Neutron Shell for the coincident detection of evaporated particles. Over 100 new g-ray transitions connecting some 50 excited states have been identified. Most of the states are built on particle-hole excitations across the shell gaps at particle number N=Z=28. The rich experimental data allows for a comprehensive comparison of core-excited states with results from large-scale shellmodel calculations, which are known to provide excellent predictions for the lower-lying yrast and near-yrast levels in 1f7/2 nuclei.