Continuum study on QCD phase diagram through an OPE-modified gluon propagator

TL;DR

This study uses an OPE-modified gluon propagator within Dyson-Schwinger equations to explore the QCD phase diagram, identifying a first order transition and a critical end point, with insights into chiral symmetry restoration.

Contribution

Introduces a gluon propagator model with quark feedback via OPE in DSEs to analyze the QCD phase diagram, highlighting the impact on the critical end point and phase transition characteristics.

Findings

Identifies a first order phase transition point on the $$ axis.

Locates the critical end point at $(T_E,_E)/T_c = (0.85,1.11)$.

Shows the pseudo-critical line's curvature decreases with increased gluon feedback.

Abstract

Within the Dyson-Schwinger equations (DSEs) framework, a gluon propagator model incorporating quark's feedback through operator product expansion (OPE) is introduced to investigate the QCD phase diagram in the temperature--chemical-potential ($T-\mu$) plane. Partial restoration of chiral symmetry at zero temperature and finite temperature are both studied, suggesting a first order phase transition point on the $\mu$ axis and a critical end point at $(T_E,\mu_E)/T_c = (0.85,1.11)$, where $T_c$ is the pseudo-critical temperature. In addition, we find the pseudo-critical line can be well parameterized with the curvature parameter $\kappa$ and a consistent decrease in $\kappa$ with more of gluon propagator distributed to quark's feedback.