Implications of comprehensive nuclear and astrophysics data on the equations of state of neutron star matter

Sk Md Adil Imam, Tuhin Malik, Constança Providência, B. K. Agrawal

Published 2024-01-11Version 1

The equations of state (EoSs) governing neutron star (NS) matter obtained for both non-relativistic and relativistic mean-field models are systematically confronted with a diverse set of terrestrial data and astrophysical observations within the Bayesian framework. The terrestrial data spans from bulk properties of finite nuclei to the heavy-ion collisions which constrain the symmetric nuclear matter EoS and the symmetry energy up to twice the saturation density ($\rho_0$= 0.16 fm$^{-3}$). The astrophysical observations encompass the NS radius, the tidal deformability, and the lower bound on maximum mass. Three sets of EoSs distributions are generated by gradually updating them with different constraints: (i) we use only the maximum NS mass, (ii) then incorporate additional terrestrial data, (iii) and finally, we include further astrophysical observations. We compare these sets using the Kullback-Liebler divergence. Our results for the Kullback-Liebler divergence highlight the significant constraints imposed on the EoSs by the currently available lower bound of neutron star maximum mass and terrestrial data. The remaining astrophysical observations further refine the EoS within the density range $\sim$ 2-3$\rho_0$.