Equations of State at Finite Temperature And Out of Equilibrium Calibrated Using Chiral Effective Field Theory

The equation of state (EoS) for nuclear matter at finite temperature and out of equilibrium is a fundamental ingredient for simulations of binary neutron star mergers, calculation of cooling curves, and other transport properties. We construct four new EoSs using a relativistic mean-field theory (RMF). Typically, the couplings in an RMF are fit to isospin-symmetric nuclear matter data, but the matter in isolated neutron stars is much closer in composition to pure neutron matter. In this work, along with reproducing isospin-symmetric nuclear matter data, we also fit our RMF to pure neutron matter calculations from chiral effective field theory. These calculations are needed because it is not possible to perform experiments on pure neutron matter on Earth. Our EoSs agree with current mass and radius measurements from NICER and LIGO.