Effect of pairing correlations on incompressibility and symmetry energy in nuclear matter and finite nuclei

The role of superfluidity in incompressibility and in symmetry energy is studied in nuclear matter and finite nuclei. Several pairing interactions are used: surface, mixed, and isovector dependent. Pairing has a small effect on the nuclear matter incompressibility at saturation density, but the effects are significant at lower densities. The pairing effect on the centroid energy of the isoscalar giant monopole resonance (GMR) is also evaluated for Pb and Sn isotopes by using a microscopic constrained-HFB approach and is found to change at most by 10% the nucleus incompressibility KA. It is shown by using the local density approximation that most of the pairing effect on the GMR centroid comes from the low-density nuclear surface.