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arXiv · 1812.06621

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

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

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 Möbius 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.

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Kei Suzuki, Sinya Aoki, Yasumichi Aoki, Guido Cossu, Hidenori Fukaya, Shoji Hashimoto. 2018-12-17. Axial U(1) symmetry and Dirac spectra in high-temperature phase of $N_f=2$ lattice QCD. https://doi.org/10.22323/1.334.0152

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