Systematics of nuclear ground-state properties of Sr isotopes by covariant density functional theory

Abstract

The hyperfine structure and isotope shifts of Sr isotopes, both even-even and odd-even nuclei, are studied in the covariant density functional theory with the new parameter set DD-PC1. Pairing correlation is treated using the Bogoliubov model with a separable form of the pairing interaction. Spin parity, charge radii, two-neutron separation energies, and pairing energies of ground states are calculated and compared with experimental data. We find a shape transition at $N\ensuremath{\approx}60$ in charge radii and spin parity, which are consistent with each other and generally agree with experiments. Although the nuclear masses are not very sensitive to these shape changes, odd-even mass differences and pairing effects are very important for study of the shape transition and shape coexistence phenomena in Sr isotopes.