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arXiv · 1711.09239

Axial $U(1)$ symmetry at high temperature in 2-flavor lattice QCD

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

We investigate the axial $U(1)_A$ symmetry breaking above the critical temperature in two-flavor lattice QCD. The ensembles are generated with dynamical M\"obius domain-wall or reweighted overlap fermions. The $U(1)_A$ susceptibility is extracted from the low-modes spectrum of the overlap Dirac eigenvalues. We show the quark mass and temperature dependences of $U(1)_A$ susceptibility. Our results at $T=220 \, \mathrm{MeV}$ imply that the $U(1)_A$ symmetry is restored in the chiral limit. Its coincidence with vanishing topological susceptibility is observed.

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Kei Suzuki, Sinya Aoki, Yasumichi Aoki, Guido Cossu, Hidenori Fukaya, Shoji Hashimoto. 2017-11-25. Axial $U(1)$ symmetry at high temperature in 2-flavor lattice QCD. https://doi.org/10.1051/epjconf/201817507025

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