Chiral condensate from a hadron resonance gas model

TL;DR

This paper investigates the chiral crossover transition in QCD using a hadron resonance gas model, incorporating lattice QCD results to improve estimates of the pseudocritical temperature and line curvature, achieving results consistent with lattice data.

Contribution

It introduces an improved criterion for estimating the pseudocritical temperature within the hadron resonance gas model, aligning well with lattice QCD findings.

Findings

Estimated pseudocritical temperature: 161.2 ± 1.7 MeV

Curvature of the pseudocritical line: 0.0203(7)

Results agree with continuum lattice QCD data

Abstract

In this work we address the question of how well the chiral crossover transition can be understood in terms of a noninteracting hadron resonance gas model. Using the latest results on the variation of hadron masses as a function of the pion mass from lattice quantum chromodynamics, we study the temperature dependence of the renormalized chiral condensate in 2+1 flavor QCD. Furthermore, we suggest a better criterion to estimate of the pseudocritical temperature, which gives $T_c = 161.2 \pm 1.7$ MeV, which is much improved compared to all the earlier results within the hadron resonance gas model or chiral perturbation theory. For the curvature of the pseudocritical line we find $\kappa_2 = 0.0203(7)$, which is in very good agreement with continuum extrapolated lattice results.