¹S₀ Nucleon Superfluidity in Neutron Star Matter

We investigate the nucleon superfluidity in the ¹S₀ channel in neutron star matter using the relativistic mean field theory and the BCS theory. We discuss particularly the influence of the isovector scalar interaction which is considered by exchanging δ meson on the nucleon superfluidity. It is found that the δ meson leads to a growth of the nucleon ¹S₀ pairing energy gaps in a middle density range of the existing nucleon superfluidity. In addition, when the density ρ_B>0.36 fm^?3, the proton ¹S₀ pairing energy gap obviously decreases. The density range of the proton ¹S₀ superfluidity is narrowed due to the presence of δ mesons. In our results, the δ meson not only changes the EOS and bulk properties but also changes the cooling properties of neutron stars.