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Dirac spectral density and mass anomalous dimension in 2+1 flavor QCD

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 نشر من قبل Katsumasa Nakayama
 تاريخ النشر 2017
  مجال البحث
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We compute the Dirac spectral density of QCD in a wide range of eigenvalues by using a stochastic method. We use 2+1 flavor lattice ensembles generated with Mobius domain-wall fermion at three lattice spacings ($a=0.083, 0.055, 0.044$ fm) to estimate the continuum limit. The discretization effect can be minimized by a generalization of the valence domain-wall fermion. The spectral density at relatively high eigenvalues can be matched with perturbation theory. We compare the lattice results with the perturbative expansion available to $O(alpha_s^4)$.



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