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arXiv · 1002.0371

Strong coupling constant from vacuum polarization functions in three-flavor lattice QCD with dynamical overlap fermions

E. Shintani·S. Aoki·H. Fukaya·S. Hashimoto·T. Kaneko·T. Onogi·N. Yamada
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Abstract

We determine the strong coupling constant $α_s$ from a lattice calculation of vacuum polarization functions (VPF) in three-flavor QCD with dynamical overlap fermions. Fitting lattice data of VPF to the continuum perturbative formula including the operator product expansion, we extract the QCD scale parameter $Λ_{\overline{MS}}^{(3)}$. At the $Z$ boson mass scale, we obtain $α_s^{(5)}(M_Z)=0.1181(3)(^{+14}_{-12})$, where the first error is statistical and the second is our estimate of various systematic uncertainties.

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E. Shintani, S. Aoki, H. Fukaya, S. Hashimoto, T. Kaneko, T. Onogi, N. Yamada. 2014-09-04. Strong coupling constant from vacuum polarization functions in three-flavor lattice QCD with dynamical overlap fermions. https://doi.org/10.1103/physrevd.82.074505%3B%2010.1103%2Fphysrevd.89.099903

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