Study of the N = 50 major shell effect toward $^{78}$Ni at PARRNe : Evidence of a weak-coupling structure in $^{83}_{32}$Ge_{51}$

NESTER; The γ-ray de-excitations following the β-decay of 83Ga and the β-n decay of 84Ga have been studied. The radioactive species were produced using the PARRNe on-line mass-separator installed at the IPN Orsay Tandem accelerator. Two γ-lines were attributed to 83Ge with the aid of β-γ and γ-γ coincidences. The Z identification of the γ-lines was provided by time analysis of a buid-up/decay cycle. The excited levels of 83Ge can be explained by the coupling of the single neutron state ν2d 5/2 to the first 2+ excitation of the 82Ge core.