The Equation of State of Dense Matter : from Nuclear Collisions to Neutron Stars

TL;DR

This paper develops a comprehensive equation of state for dense matter, combining nuclear, hyperonic, and quark matter models, to better understand neutron star properties and heavy ion collisions.

Contribution

It introduces a unified EoS incorporating nucleons, hyperons, and quark matter using multiple models, and evaluates neutron star maximum masses.

Findings

Maximum neutron star mass not exceeding 1.7 solar masses

Dense matter EoS should be soft at low density and stiff at high density

Comparison with data supports the proposed EoS behavior

Abstract

The Equation of State (EoS) of dense matter represents a central issue in the study of compact astrophysical objects and heavy ion reactions at intermediate and relativistic energies. We have derived a nuclear EoS with nucleons and hyperons within the Brueckner-Hartree-Fock approach, and joined it with quark matter EoS. For that, we have employed the MIT bag model, as well as the Nambu--Jona-Lasinio (NJL) and the Color Dielectric (CD) models, and found that the NS maximum masses are not larger than 1.7 solar masses. A comparison with available data supports the idea that dense matter EoS should be soft at low density and quite stiff at high density.