Exploration of the phase diagram and the thermodynamic properties of QCD at finite temperature and chemical potential with the PNJL effective model

TL;DR

This paper uses the PNJL effective model to explore the QCD phase diagram, identifying the critical line and endpoint by analyzing thermodynamic quantities and fluctuations at finite temperature and chemical potential.

Contribution

It applies the 2+1 flavor PNJL model in Mean Field Approximation to map the QCD phase diagram and locate the critical endpoint.

Findings

Identification of the critical line in the phase diagram.

Detection of the critical endpoint through fluctuation analysis.

Thermodynamic quantities computed across the phase transition.

Abstract

The QCD transition from a hadronic to a quark-gluon plasma phase is a cross-over at vanishing/small baryo-chemical potential, while at higher chemical potentials it is argued that it becomes of first order, ending with a critical end-point. The present goal is the determination of the critical line and, possibly, the recognition of the critical endpoint. For this purpose, the effective model (Nambu-Jona-Lasinio model with Polyakov Loop) with 2+1 flavours is used. In Mean Field Approximation it is possible to obtain all thermodynamic quantities (pressure, entropy, energy and quark density) and their fluctuations, in particular, the generalized quark-number susceptibilities. We use the net baryon-number fluctuations and net-strangeness fluctuations to identify the critical line and the order of the phase transition in the chemical potential - temperature plane.