Reparametrizing the Polyakov$-$Nambu$-$Jona-Lasinio model

TL;DR

This paper reparametrizes the Polyakov-Nambu-Jona-Lasinio model to better match recent lattice QCD data, achieving excellent agreement for the equation of state but noting some discrepancies in susceptibilities and correlations.

Contribution

It introduces a reparametrization approach for the Polyakov-Nambu-Jona-Lasinio model to align its predictions with latest lattice QCD results.

Findings

Excellent agreement with lattice data for the equation of state.

Remaining discrepancies in susceptibilities and correlations.

Discussion of causes and future directions for improvements.

Abstract

The Polyakov$-$Nambu$-$Jona-Lasinio model has been quite successful in describing various qualitative features of observables for strongly interacting matter, that are measurable in heavy-ion collision experiments. The question still remains on the quantitative uncertainties in the model results. Such an estimation is possible only by contrasting these results with those obtained from first principles using the lattice QCD framework. Recently a variety of lattice QCD data were reported in the realistic continuum limit. Here we make a first attempt at reparametrizing the model so as to reproduce these lattice data. We find excellent quantitative agreement for the equation of state. Certain discrepancies in the charge and strangeness susceptibilities as well as baryon-charge correlation still remain. We discuss their causes and outline possible directions to remove them.