Topological Susceptibility in $N_f=2$ QCD at Finite Temperature

TL;DR

This study investigates the behavior of topological susceptibility in two-flavor QCD at finite temperature, revealing suppression at low quark masses and discussing implications for $U_A(1)$ symmetry restoration.

Contribution

It provides new insights into the temperature and quark mass dependence of topological susceptibility in $N_f=2$ QCD using M"obius domain-wall fermions.

Findings

Topological susceptibility is suppressed below a certain quark mass at finite temperature.

The suppression correlates with the restoration of $U_A(1)$ symmetry.

Results are consistent across different definitions of topological charge.

Abstract

We study the topological charge in $N_f=2$ QCD at finite temperature using M\"obius domain-wall fermions. The susceptibility $\chi_t$ of the topological charge defined either by the index of overlap Dirac operator or a gluonic operator is investigated at several values of temperature $T\ (>T_c)$ varying the quark mass. A strong suppression of the susceptibility is observed below a certain value of the quark mass. The relation with the restoration of $U_A(1)$ is discussed.