Study of the effect of the tensor correlation in oxygen isotopes with the charge- and parity-projected Hartree-Fock method

Abstract

Recently, we developed a mean-field-type framework which treats the correlation induced by the tensor force. To exploit the tensor correlation we introduce single-particle states with the parity and charge mixing. To make a total wave function have a definite charge number and a good parity, the charge number and parity projections are performed. Taking a variation of the projected wave function with respect to single-particle states a Hartree-Fock-like equation, the charge- and parity-projected Hartree-Fock equation, is obtained. In the charge- and parity-projected Hartree-Fock method, we solve the equation selfconsistently. In this paper we extend the charge- and parity-projected Hartree-Fock method to include a three-body force, which is important to reproduce the saturation property of nuclei in mean-field frameworks. We apply the charge- and parity-projected Hartree-Fock method to sub-closed-shell oxygen isotopes (14O, 16O, 22O, 24O, and 28O) to study the effect of the tenor correlation and its dependence on neutron numbers. We obtain reasonable binding energies and matter radii for these nuclei. It is found that relatively large energy gains come from the tensor force in these isotopes and there is the blocking effect by occupied neutron orbits on the tensor correlation.