Experimental study of the β - γ and β - nγ decay of the neutron-rich nucleus 85Ga

The beta-decay properties of neutron-rich Ga-85 produced in proton-induced fission of U-238 were studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. Data consisted of beta - gamma and beta - gamma - gamma coincidences were collected at the Low-energy Radioactive Ion Beam Spectroscopy Station after high-resolution on-line mass separation. For the first time, the excited states in the N = 53 isotone Ge-85 were established from beta-delayed gamma decay of Ga-85. The level scheme of the N = 52 isotone Ge-84 was improved and includes now 0(+), 2(+), (2)(+), 4(+), and (0)(+) states populated in the beta-delayed-neutron-gamma decay of Ga-85. Advanced shell-model calculations were used to analyze experimental data on Ge-85 and Ge-84.