Superfluidity of -Hyperons Admixed in Neutron Star Cores

Abstract

Λ-superfluidity in a hyperon core of neutron stars is studied with a realistic approach. It is found that Λ-superfluid exists in a restricted density region ρ≃(ρ<inf>t</inf>–ρ<inf>d</inf>) with ρ<inf>t</inf>≃2ρ<inf>0</inf> (ρ<inf>0</inf> being the nuclear density) and ρ<inf>d</inf>≃(2.6–4.6)ρ<inf>0</inf> depending on the pairing interaction and the hyperon core model. This restriction suggests that neutron stars compatible with hyperon cooling would be not so massive.