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arXiv · 1908.11684

Axial U(1) symmetry, topology, and Dirac spectra at high temperature in $N_f=2$ lattice QCD

Kei Suzuki·Sinya Aoki·Yasumichi Aoki·Guido Cossu·Hidenori Fukaya·Shoji Hashimoto
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Abstract

Using lattice QCD simulations with $N_f = 2$ dynamical fermions, we study the axial $U(1)$ symmetry, topological charge, and Dirac eigenvalue spectra in the high-temperature phase in which the chiral symmetry is restored. Our gauge ensembles are generated with Möbius domain-wall fermions, but the measurements such as susceptibilities are reweighted to those for the overlap fermions by using overlap/domain-wall reweighting technique. We find that the $U(1)_A$ and topological susceptibilities are strongly suppressed in the small quark mass region, which is related to the reduction of chiral-zero and low-nonzero modes on the Dirac spectra. We also examine their volume dependence.

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Kei Suzuki, Sinya Aoki, Yasumichi Aoki, Guido Cossu, Hidenori Fukaya, Shoji Hashimoto. 2019-08-29. Axial U(1) symmetry, topology, and Dirac spectra at high temperature in $N_f=2$ lattice QCD. https://doi.org/10.22323/1.317.0085

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