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Strong coupling constant from $τ$ decay within renormalization scheme invariant treatment

J. G. Koerner·F. Krajewski·A. A. Pivovarov
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Abstract

We extract a numerical value for the strong coupling constant α_s from the τ-lepton decay rate into nonstrange particles. A new feature of our procedure is the explicit use of renormalization scheme invariance in analytical form in order to perform the actual analysis in a particular renormalization scheme. For the reference coupling constant in the \MSsch-scheme we obtain α_s(M_τ)= 0.3184 \pm 0.0060_{exp} which corresponds to \al_s(M_Z)= 0.1184 \pm 0.0007_{exp} \pm 0.0006_{hq mass}. This new numerical value is smaller than the standard value from $τ$-data quoted in the literature and is closer to \al_s(M_Z)-values obtained from high energy experiments.

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J. G. Koerner, F. Krajewski, A. A. Pivovarov. 2000-11-27. Strong coupling constant from $τ$ decay within renormalization scheme invariant treatment. https://doi.org/10.1103/physrevd.63.036001

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