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arXiv · 1012.4052

Determination of the chiral condensate from QCD Dirac spectrum on the lattice

H. Fukaya·S. Aoki·T. W. Chiu·S. Hashimoto·T. Kaneko·J. Noaki·T. Onogi·N. Yamada
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Abstract

We calculate the chiral condensate of QCD with 2, 2+1 and 3 flavors of sea quarks. Lattice QCD simulations are performed employing dynamical overlap fermions with up and down quark masses covering a range between 3 and 100 MeV. On L ~ 1.8-1.9 fm lattices at a lattice spacing ~ 0.11 fm, we calculate the eigenvalue spectrum of the overlap-Dirac operator. By matching the lattice data with the analytical prediction from chiral perturbation theory at the next-to-leading order, the chiral condensate in the massless limit of up and down quarks is determined.

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H. Fukaya, S. Aoki, T. W. Chiu, S. Hashimoto, T. Kaneko, J. Noaki, T. Onogi, N. Yamada. 2010-12-18. Determination of the chiral condensate from QCD Dirac spectrum on the lattice. https://doi.org/10.1103/physrevd.83.074501

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