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

We studied the β-decay properties of neutron-rich 85Ga produced in proton-induced fission of 238U at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. Data consisted of β-γ and β-γ-γ 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 85Ge were established from β-delayed γ decay of 85Ga. The level scheme of the N=52 isotone 84Ge was improved and includes now 0+, 2+, (2)+, 4+, and (0)+ states populated in the β-delayed-neutron-γ decay of 85Ga. Advanced shell-model calculations were used to analyze experimental data on 85Ge and 84Ge.