Tilted-axis-cranking covariant density functional theory for the high-spin spectroscopy in 69Ga

The tilted-axis-cranking covariant density functional theory is applied to investigate the three newly-observed positive-parity bands SI, SII, and SIII in 69Ga. The energy spectra and angular momenta are calculated and good agreements with the experimental data are realized. For the band SI, pairing correlations play a crucial role for the states with spin I≦23/2. The bands SII and SIII are suggested to be signature partner bands with positive and negative signatures, respectively. By analyzing the angular momentum alignments, it is revealed that the g9/2 protons and neutrons play an important role in the collective structures of 69Ga. The transition probabilities B(E2) for these bands are predicted, awaiting further experimental verification.