Universal critical behavior and the transition temperature in (2+1)-flavor QCD

TL;DR

This paper investigates the universal critical behavior in (2+1)-flavor QCD using lattice data, confirming expected scaling and estimating the transition temperature across different lattice discretizations and quark masses.

Contribution

It provides new lattice QCD results demonstrating universal scaling of the chiral condensate and offers a preliminary estimate of the QCD transition temperature.

Findings

Chiral condensate shows universal scaling near the critical point.

Estimated QCD transition temperature from susceptibility analysis.

Consistent results across different lattice discretizations and spacings.

Abstract

We discuss the universal critical behavior in (2+1)-flavor QCD by analyzing lattice data from improved staggered fermions generated by the HotQCD Collaboration. We present recent results from two different lattice discretizations and various lattice spacings ($N_\tau=6,8,12$) at fixed physical strange quark mass ($m_s$) but varying light quark mass ($m_l$). We find that the chiral order-parameter, i.e. the chiral condensate, shows the expected universal scaling that is associated with the critical point in the chiral limit already for light quark masses $m_l/m_s \lsim 0.05$. From an analysis of the disconnected chiral susceptibility we estimate a preliminary value of the QCD transition temperature.