Propagators and phase structure of Nf=2 and Nf=2+1 QCD

TL;DR

This paper studies the phase diagram of QCD with two and three flavors by solving Dyson-Schwinger equations, including full quark back-reaction and strange quark effects, and finds a potential critical endpoint at finite chemical potential.

Contribution

It introduces a comprehensive Dyson-Schwinger approach that incorporates full quark back-reaction and strange quark effects to analyze QCD phase transitions.

Findings

Agreement with lattice results for quark condensate at zero chemical potential

Identification of a potential critical endpoint at (mu_q,T) = (190,100) MeV

Analysis of the unquenched gluon propagator's thermal mass

Abstract

We investigate the phase structure of QCD at finite temperature and chemical potential by solving a coupled set of truncated Dyson-Schwinger equations for the quark and gluon propagator. In contrast to previous calculations we take into account the full back-reaction of the quarks onto the Yang-Mills sector and we include the effects of strange quarks. We discuss the resulting thermal mass of the unquenched gluon propagator and extract order parameters for the chiral and deconfinement transition from the quarks. Our result for the temperature dependence of the quark condensate at zero chemical potential agrees well with corresponding lattice calculations. We determine the phase diagram at finite chemical potential and find a potential critical endpoint at (mu_q,T) = (190,100) MeV.