Potential Depth of Σ-hyperons in Saturated Nuclear Matter and Rotational Inertia of Proto Neutron Star†

In the framework of relativistic mean field theory and taking account of the baryon octet system {n, p,Λ,Σ−,Σ0,Σ+, Ξ−, Ξ0}, the influence of the potential depth U(N) Σ of Σ-hyperon in saturated nuclear matter on the rotational inertia of proto neutron star (PNS) is investigated. It is found that the rotational inertia corresponding to the maximum mass of PNS increases, respectively, by a factor of 0.44%, 0.29% and 0.08%, for the attractive potential depth U(N) Σ = -30 MeV, -20MeV, -10MeV and 0MeV, and increases by a factor of 0.06% and 0.08% for the repulsive potential depth U(N) Σ = + 10MeV, + 20MeV and + 30 MeV. The effect of the attractive (negative) potential depth U(N) Σ on the rotational inertia corresponding to the maximum mass of PNS is several times larger than that of the repulsive (positive) one.