Structure ofCo65,67studied through theβdecay ofFe65,67and a deep-inelastic reaction

Abstract

The neutron-rich isotopes {sup 65,67}Fe and {sup 65}Co have been produced at the LISOL facility, Louvain-La-Neuve, in the proton-induced fission of {sup 238}U. Beams of these isotopes have been extracted with high selectivity by means of resonant laser ionization combined with mass separation. Yrast and near-yrast levels of {sup 65}Co have also been populated in the {sup 64}Ni+{sup 238}U reaction at Argonne National Laboratory. The level structure of {sup 65}Co could be investigated by combining all the information from both the {sup 65}Fe and {sup 65}Co{beta} decay and the deep-inelastic reaction. The {sup 65}Fe, {sup 65}Co, and {sup 67}Fe decay schemes and the {sup 65}Co yrast structure are fully established. The {sup 65,67}Co level structures can be interpreted as resulting from the coexistence of core-coupled states with levels based on a low-energy proton-intruder configuration.