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Three-loop beta function and non-perturbative $α_s$ in asymmetric momentum scheme

Ph. Boucaud·J. P. Leroy·J. Micheli·O. Pene·C. Roiesnel
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Abstract

We determine the three-loop coefficient of the beta function in the asymmetric momentum subtraction scheme in Landau gauge. This scheme is convenient for lattice studies of α_s, the running coupling constant of QCD. We present high statistics lattice results for α_s in the SU(3) Yang-Mills theory without quark, compare with the three-loop running and extract the value of the corresponding Λ_\msbar parameter. We estimate the systematic error coming from four-loop terms. We obtain the result: Λ_\msbar = 295 (5) (15) {a^{-1}(β=6.0) \over 1.97 GeV} MeV.

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Ph. Boucaud, J. P. Leroy, J. Micheli, O. Pene, C. Roiesnel. 1999-01-05. Three-loop beta function and non-perturbative $α_s$ in asymmetric momentum scheme. https://doi.org/10.1088/1126-6708%2F1998%2F12%2F004

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