Towards a parameter-free analysis of the QCD chiral phase transition and its universal critical behavior

TL;DR

This paper introduces a parameter-free method to analyze the universal critical behavior of the QCD chiral phase transition, accurately determining the transition temperature and critical exponent using improved order parameters.

Contribution

It develops a renormalized, divergence-free order parameter and constructs ratios to extract critical properties independently of parameters, advancing the understanding of QCD phase transitions.

Findings

Estimated chiral transition temperature $T_c$ on $N_ au=8$ lattices.

Determined the critical exponent $ ext{delta}$ for the universality class.

First numerical results using improved order parameters in lattice QCD.

Abstract

To quantify the universal properties of chiral phase transition in (2+1)-flavor QCD, we use an improved, renormalized order parameter for the chiral symmetry breaking. We construct ratios of this divergence-free order parameter from its values for different pairs of light quark masses. From this, we determine in a parameter-independent manner, the chiral phase transition temperature $T_c$ and the associated critical exponent $\delta$ of the universality class. We present first numerical results of these calculations on $N_\tau=8$ lattices, with staggered fermions.