beta decay of neutron-rich 76Cu and the structure of 76Zn

The beta decay of 76Cu to the levels of 76Zn was studied at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Lab (ORNL). A purified 76Cu beam was developed and data were recorded for the decay of the A = 76 decay chain using four high-purity germanium (HPGe) clover detectors at the Low-energy Radioactive Ion Beam Spectroscopy Station (LeRIBSS). In this measurement, data on gamma-ray emission following beta decay, including beta gamma and gamma gamma coincidences, were collected and gamma gamma spectra were analyzed to identify the statistically significant coincidences. From this analysis, we propose a level scheme for 76Zn which contains a total of 59 energy levels up to 6.0 MeV containing 105 gamma rays. We have identified an additional 53 gamma rays associated with this decay which could not be place in the decay scheme due to insufficient coincidence information or no energy match to identified levels. No gamma rays from states in 75Zn fed in the delayed-neutron branch were observed even though other gamma rays in the A = 75 decay chain were observed. Spin and parity assignments are proposed for some levels based on comparison to systematics and shell model calculations.