Axial U(1) symmetry at high temperatures in $N_f=2+1$ lattice QCD with chiral fermions

TL;DR

This study investigates the fate of the axial U(1) symmetry in high-temperature lattice QCD with 2+1 flavors using chiral fermions, analyzing spectral and topological properties.

Contribution

It provides new insights into the U(1)_A anomaly at high temperatures by using reweighted overlap fermions on M"obius domain-wall ensembles.

Findings

U(1)_A susceptibility decreases with temperature

Overlap Dirac spectrum shows suppression of near-zero modes

Topological susceptibility is consistent with U(1)_A restoration

Abstract

We study the $U(1)_A$ anomaly in the high-temperature phase of $N_f=2+1$ lattice QCD with chiral fermions. Gauge ensembles are generated with M\"obius domain-wall (MDW) fermions, and in the measurements the determinant is reweighted to that of overlap fermions. We report the results for the overlap Dirac spectrum, $U(1)_A$ susceptibility, and topological susceptibility at $T=204$ and $175$ MeV.