Net-baryon number fluctuations in (2+1)-flavor QCD

TL;DR

This study investigates net-baryon number fluctuations in (2+1)-flavor QCD using lattice simulations, revealing how fluctuations behave near the critical temperature and estimating the transition line's curvature.

Contribution

It provides the first lattice-based analysis of higher moments of net-baryon fluctuations and their relation to critical behavior in QCD.

Findings

Fluctuations agree with resonance gas predictions below 0.9T_c.

Higher moments are sensitive to critical behavior near T_c.

Estimated the radius of convergence and transition line curvature.

Abstract

We present a lattice study of net-baryon number fluctuations in (2+1)-flavor QCD. The results are based on a Taylor expansion of the pressure with respect to the baryon chemical potential. We calculate higher moments of the net-baryon number fluctuations and compare with the corresponding resonance gas results. We find that for temperature below 0.9T_c the fluctuations seem to agree with the hadron resonance gas predictions. Close to T_c, higher moments are increasingly more sensitive to the critical behavior of the QCD phase transition. Furthermore, we estimate the radius of convergence of the Taylor series as well as the curvature of the transition line in the temperature chemical potential plane.