Axial U(1) symmetry and Dirac spectra in high-temperature phase of $N_f=2$ lattice QCD

Understand

The axial $U(1)$ symmetry in the high-temperature phase is investigated with $N_f = 2$ lattice QCD simulations.

• The gauge ensembles are generated with M\"obius domain-wall fermions, and the overlap/domain-wall reweighting is applied.
• We find that the $U(1)_A$ susceptibility evaluated from the spectrum of overlap-Dirac eigenvalues is strongly suppressed in the chiral limit.
• We also study its volume dependence.