Quark matter in Neutron Stars within the Field Correlator Method

TL;DR

This paper investigates how quark matter could exist in neutron star cores using the Field Correlator Method, and how recent heavy neutron star observations constrain quark matter model parameters.

Contribution

It extends the Field Correlator Method to zero temperature and explores parameter dependencies affecting neutron star maximum mass predictions.

Findings

Maximum neutron star mass depends strongly on V_1 and G_2 parameters.

Model predictions are consistent with observations for sufficiently large V_1.

The study links quark matter properties to astrophysical constraints.

Abstract

We discuss the appearance of quark matter in neutron star cores', focussing on the possibility that the recent observation of a very heavy neutron star could constrain free parameters of quark matter models. For that, we use the equation of state derived with the Field Correlator Method, extended to the zero temperature limit, whereas for the hadronic phase we use the equation of state obtained within both the non-relativistic and the relativistic Brueckner-Hartree-Fock many-body theory. We find a strong dependence of the maximum mass both on the value of the q\bar q interaction V_1, and on the gluon condensate G_2, for which we introduce a dependence on the baryon chemical potential mu_B. We find that the maximum masses are consistent with the observational limit for not too small values of V_1.