Excluded Volume Effects in Proto-Neutron Stars

Relativistic Mean Field (RMF) models are understood to require rather strong vector repulsion to reproduce finite density data related to neutron stars and nuclear saturation properties. This translates into a dependence of interaction terms on the net baryon density. The latter evidently does not contribute at zero baryon density at any given temperature. In this domain, the Hadron Resonance Model (HRM) improves if repulsion effects are incorporated in the form of excluded volume of Hadrons. We present a model inspired by the RMF model, that considers both the standard RMF vector repulsion and excluded volume-related effects, and analyze the effect on neutron and proto-neutron stars.