Speaker
Description
We constrain the equation of state (EoS) of dense nuclear matter using a relativistic mean-field (RMF) model within a Bayesian inference framework. Constraints from chiral effective field theory ($\chi$-EFT), the observed maximum neutron star mass ($\sim 2 M_\odot$), gravitational-wave data from GW170817, and NICER X-ray mass–radius measurements are combined to obtain posterior distributions for nuclear saturation properties and RMF coupling constants. These posteriors are used to predict neutron skin thicknesses of ${}^{48}$Ca and ${}^{208}$Pb. Our analysis indicates that GW170817 and recent NICER observations favor a relatively soft EoS, leading to lower crust-core transition densities and thinner neutron star crusts. The radius of a $1.4 M_\odot$ neutron star is constrained to $12.51_{0.24}^{+0.26}$ km, while the maximum mass reaches $2.17_{−0.12}^{+0.17} M_\odot$. We find that the $\omega-\rho$ coupling becomes increasingly important under successive astrophysical constraints. The predicted neutron skin thickness of ${}^{48}$Ca agrees with CREX, whereas ${}^{208}$Pb remains in tension with PREX-II. We did not find any clear correlation between the skin thickness of ${}^{208}$Pb and the symmetry energy slope parameter $L$, unlike earlier studies.
