2004A&A...423.1063G

We simulate cooling of superfluid neutron stars with nucleon cores where the direct Urca process is forbidden. We adopt density-dependent critical temperatures T_cp(ρ) and T_cn(ρ) of singlet-state proton and triplet-state neutron pairing in a stellar core and consider strong proton pairing (with maximum T_cp^max>5x10⁹K) and moderate neutron pairing (T_cn^max∼6x10⁸K). When the internal stellar temperature T falls below T_cn^max, the neutrino luminosity L_CP due to Cooper pairing of neutrons behaves ∝ T⁸, just as that produced by the modified Urca process (in a non-superfluid star) but is higher by about two orders of magnitude. In this case the Cooper-pairing neutrino emission acts like an enhanced cooling agent. By tuning the density dependence T_cn(ρ) we can explain observations of cooling isolated neutron stars in the scenario in which the direct Urca process or a similar process in kaon/pion condensed or quark matter are absent.