Microsecond isomers beyond 68Ni

Excited states in the nuclei with Z∼28 and N∼40 have been studied. These neutron-rich nuclei have been produced in the fragmentation reaction of a 86Kr beam at 60.3 MeV/ nucl. The decays of isomers populated in the fragmentation are detected at the final focus of the spectrometer in event-by-event microsecond correlation with identified recoils. Several new isomers with half-lives ∼300 ns have been discovered including the very exotic 78mZn. A puzzling result of the performed experiment, the non-observation of expected Iπ=8+ isomers in 72Ni and 74Ni nuclei is also reported.