^{1}S_{0} proton superfluidity in neutron star matter: Impact of bulk   properties
  We study the ^{1}S_{0} proton pairing gap in neutron star matter putting emphasis on influence of the Dirac effective mass and the proton fraction on the gap within the relativistic Hartree-Bogoliubov model. The gap equation is solved using the Bonn-B potential as a particle-particle channel interaction. It is found that the maximal pairing gap \Delta_{max} is 1-2 MeV, which has a strong correlation with the Dirac effective mass. Hence we suggest that it serves as a guide to narrow down parameter sets of the relativistic effective field theory. Furthermore, the more slowly protons increase with density in the core region of neutron stars, the wider the superfluid range and the slightly lower the peak of the gap become. 
Tomonori Tanigawa (JSPS, JAERI), Masayuki Matsuzaki (Fukuoka   University of Education), Satoshi Chiba (JAERI)