Phase diagram and critical endpoint for strongly-interacting quarks

TL;DR

This paper presents a novel method using chiral susceptibility to map the phase diagram of strongly-interacting quarks, accurately locating the critical endpoint and analyzing phase coexistence behavior.

Contribution

It introduces a versatile approach applicable with any gap equation to determine the phase diagram and critical endpoint in quark matter.

Findings

Critical endpoint located at (.0,0.9)T_c.

Phase coexistence domain expands with increasing confinement length-scale.

Method applicable even with unknown quark-gluon vertex diagrammatic content.

Abstract

We introduce a method based on the chiral susceptibility, which enables one to draw a phase diagram in the chemical-potential/temperature plane for strongly-interacting quarks whose interactions are described by any reasonable gap equation, even if the diagrammatic content of the quark-gluon vertex is unknown. We locate a critical endpoint (CEP) at (\mu^E,T^E) ~ (1.0,0.9)T_c, where T_c is the critical temperature for chiral symmetry restoration at \mu=0; and find that a domain of phase coexistence opens at the CEP whose area increases as a confinement length-scale grows.