Constraining isoscalar-vector and isovector-vector couplings from very heavy neutron stars and GW190814 observations
Phys. Rev. C 113, 025801 – Published 2 February, 2026
DOI: https://doi.org/10.1103/b6ty-m1sj
Abstract
We constrain the nuclear matter equation of state (EOS) within the relativistic mean field model by including the isoscalar-vector and isovector-vector coupling term at a fundamental level using Bayesian analysis. We utilized the nuclear saturation properties and recent astrophysical observations to constrain the EOS of dense matter. We obtained approximately 20 000 sets of equations of state from sampling about sets of equations of state. All 20 000 equations of state satisfy nuclear matter saturation properties at saturation densities and produce high mass neutron stars (NSs). In our findings, we find that the nonzero value of the scalar-vector and isovector-vector coupling parameter and the negative value of the sigma meson self-coupling stiffen the EOS. Our sets of equations of state produce NSs of mass larger than to include the recent gravitational waves observation GW190814.
