Bayesian inference of neutron-star observables based on effective nuclear interactions

Abstract

Based on the Skyrme-Hartree-Fock model (SHF) as well as its extension [the Korea-IBS-Daegu-SKKU (KIDS) model] and the relativistic mean-field (RMF) model, we have studied the constraints on the parameters of the nuclear matter equation of state (EOS) from adopted astrophysical observables using a Bayesian approach. While the masses and radii of neutron stars generally favor a stiff isoscalar EOS and a moderately soft nuclear symmetry energy, model dependence on the constraints is observed and mostly originates from the incorporation of higher-order EOS parameters and differences between relativistic and nonrelativistic models. At twice saturation density, the value of the symmetry energy is constrained to be ${48}_{\ensuremath{-}11}^{+15}\phantom{\rule{4pt}{0ex}}\mathrm{MeV}$ in the standard SHF model, ${48}_{\ensuremath{-}15}^{+8}\phantom{\rule{4pt}{0ex}}\mathrm{MeV}$ in the KIDS model, and ${48}_{\ensuremath{-}6}^{+5}\phantom{\rule{4pt}{0ex}}\mathrm{MeV}$ in the RMF model, around their maximum a posteriori values within $68%$ confidence intervals. Our study helps to obtain a robust constraint on nuclear matter EOS, and, meanwhile, to understand the model dependence of the results.