proton superfluidity in neutron star matter; Impact of bulk properties

Tanigawa, Tomonori; Matsuzaki, Masayuki*; Chiba, Satoshi

We study the proton pairing gap in neutron star matterputting emphasis on influence of the Dirac effective mass and theproton fraction on the gap within the relativistic Hartree-Bogoliubovmodel. The gap equation is solved using the Bonn-B potential as aparticle-particle channel interaction. It is found that the maximalpairing gap is 1-2MeV, which has a strongcorrelation with the Dirac effective mass. Hence we suggest that itserves as a guide to narrow down parameter sets of the relativisticeffective field theory. Furthermore, the more slowly protons increasewith density, the lower the peak of the gap and the wider thesuperfluid range become.