Isoscalar pairing correlations by the tensor force in the ground states of C-12, O-16, Ne-20, and S-32 nuclei

Abstract

We investigate roles of the tensor force (TF) on the pairing correlations in the ground-state structure of C-12, O-16, Ne-20, and S-32 nuclei within a deformed BCS model. For pairing matrix elements, we exploit the Brueckner G matrix derived from the charge-dependent Bonn potential. In particular, the isoscalar (IS) neutron-proton (np) pairing is studied in detail in relation to spin-triplet even TF in the nucleon-nucleon interaction. Detailed analyses of the np pairing and possible enhancement of the IS channel are performed by focusing on roles of attractive spin-triplet even and repulsive spin-triplet odd channels in the TF for the ground states of the nuclei with some deformation. It is also shown that the TF may play a crucial role of properly interpreting the experimental data of a two-nucleon knockout reaction from C-12.