Abstract. We present sets of equation of state (EOS) of nuclear matter including hyperons using an SU f (3) extended relativistic mean field (RMF) model with a wide coverage of density, temperature, and charge fraction for numerical simulations of core collapse supernovae. Coupling constants of Σ and Ξ hyperons with the σ meson are determined to fit the hyperon potential depths in nuclear matter, U Σ (ρ 0 ) ≃ +30MeV and U Ξ (ρ 0 ) ≃ −15MeV, which are suggested from recent analyses of hyperon production reactions. At low densities, the EOS of uniform matter is connected with the EOS by Shen et al., in which formation of finite nuclei is included in the Thomas-Fermi approximation. In the present EOS, the maximum mass of neutron stars decreases from 2.17M ⊙ (N eµ) to 1.63M ⊙ (N Y eµ) when hyperons are included. In a spherical, adiabatic collapse of a 15M ⊙ star by the hydrodynamics without neutrino transfer, hyperon effects are found to be small, since the temperature and density do not reach the region of hyperon mixture, where the hyperon fraction is above 1 % (T > 40MeV or ρ B > 0.4 fm −3 ).

We examine possibilities of pion condensation with zero momentum (s-wave condensation) in neutron stars by using the pion-nucleus optical potential U and the relativistic mean field (RMF) models. We use low-density phenomenological optical potentials parameterized to fit deeply bound pionic atoms or pion-nucleus elastic scatterings. Proton fraction (Yp) and electron chemical potential (µe) in neutron star matter are evaluated in RMF models. We find that the s-wave pion condensation hardly takes place in neutron stars and especially has no chance if hyperons appear in neutron star matter and/or b1 parameter in U has density dependence. PACS numbers: 21.65.Jk, 36.10.Gv, 25.80.Dj,

We develop a chiral SU(3) symmetric relativistic mean field model with a logarithmic potential of scalar condensates. Experimental and empirical data of symmetric nuclear matter saturation properties, bulk properties of normal nuclei, and separation energies of single-and double-hypernuclei are well explained. The nuclear matter equation of state (EOS) is found to be softened by σ ζ mixing which comes from determinant interaction. The neutron star matter EOS is further softened by hyperons.

Abstract. We study the hyperon-nucleus potential with distorted wave impulse wave approximation (DWIA) using Green's function method. In order to include the nucleon and hyperon potential effects in Fermi averaging, we introduce the local optimal momentum approximation of target nucleons. We can describe the quasi free Λ, Σ and Ξ production spectra in a better way than in the standard Fermi averaged t-matrix treatments.

We develop a relativistic mean field (RMF) model with explicit three-body couplings and apply it to hyperonic systems and neutron star matter. Three-baryon repulsion is a promising ingredient to answer the massive neutron star puzzle; when strange hadrons such as hyperons are taken into account, the equation of state (EOS) becomes too soft to support the observed two-solar-mass neutron star. We demonstrate that it is possible to consistently explain the massive neutron star and hypernuclear data when we include three-body couplings and modify the hyperon-vector meson couplings from the flavor SU(3) value.