Core polarization for the electric quadrupole moment of neutron-rich Aluminum isotopes

Abstract

The core polarization effect for the electric quadrupole moment of the neutron-rich ${}^{31}$Al, ${}^{33}$Al and ${}^{35}$Al isotopes in the vicinity of the island of inversion are investigated by means of the microscopic particle-vibration coupling model in which the Skyrme Hartee-Fock-Bogoliubov and quasiparticle-random-phase approximation are used to calculate the single-quasiparticle wave functions and the excitation modes. It is found that the polarization charge for the proton $1d_{5/2}$ hole state in ${}^{33}$Al is quite sensitive to coupling to the neutrons in the $pf$-shell associated with the pairing correlations, and that the polarization charge in ${}^{35}$Al becomes larger due to the stronger collectivity of the low-lying quadrupole vibrational mode in the neighboring ${}^{36}$Si nucleus.

Comments: Submitted to Phys. Rev. C