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Running electromagnetic coupling constant: low energy normalization and the value at M_Z

A. A. Pivovarov
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Abstract

A numerical value for the running electromagnetic coupling constant in the MS scheme is calculated at the low energy normalization scale equal to the tau-lepton mass M_τ. This low energy boundary value is used for running the electromagnetic coupling constant to larger scales where high precision experimental measurements can be performed. Particular scales of interest are the b-quark mass for studying the Υ-resonance physics and the Z-boson mass M_Z for high precision tests of the standard model and for the Higgs mass determination from radiative corrections. A numerical value for the running electromagnetic coupling constant at M_Z in the on-shell renormalization scheme is also given.

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A. A. Pivovarov. 2000-11-09. Running electromagnetic coupling constant: low energy normalization and the value at M_Z. https://doi.org/10.1134/1.1495645

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