Finite-size effects in the gap equation for Paris interaction

Abstract

Abstract The pairing problem in nuclei is approached starting from a realistic nucleon-nucleon interaction and solving the full gap equation in a complete basis. To this purpose the original bare nucleon-nucleon interaction, a separable form of the Paris potential, in the 1 S 0 channel is first renormalized into a large spherical Woods-Saxon basis which includes single-particle levels up to 100 MeV. The corresponding matrix elements in the Woods-Saxon basis are then used to solve exactly the gap equation. Proton and neutron gaps are computed for Cr and Fe isotopes. Finite-size effects are evidenced.