Phase diagram of hot and dense QCD constrained by the Statistical Model

TL;DR

This paper introduces a method to constrain the QCD phase diagram by integrating the Statistical Model with the PNJL model, ensuring a smooth transition from hadronic to quark-gluon degrees of freedom, and finds the chiral transition occurs at higher temperatures than deconfinement.

Contribution

It proposes a novel prescription to constrain the chiral effective model using the Statistical Model, improving the understanding of the QCD phase diagram and the transition region.

Findings

Chiral phase transition occurs at slightly higher temperature than deconfinement.

Overlap region constrains model uncertainties.

Supports a smooth transition from hadrons to quarks and gluons.

Abstract

We propose a prescription to constrain the chiral effective model approach to the QCD phase diagram using the thermal Statistical Model, which is a description consistent with the experimental data at the freeze-out. In the transition region where thermal quantities of hadrons blow up, deconfined quarks and gluons should smoothly take over the degrees of freedom from hadrons in the Statistical Model. We use the Polyakov-loop coupled Nambu--Jona-Lasinio (PNJL) model as an effective description in the quark side. We require that the validity regions of these descriptions should have an overlap on the phase diagram, which constrains model uncertainty. Our results favor a phase diagram with the chiral phase transition located at slightly higher temperature than deconfinement.