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Exact gauge invariant mass dependence of α_s through two loops

Michael Melles
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Abstract

A physically defined QCD coupling parameter naturally incorporates massive quark flavor thresholds in a gauge invariant, renormalization scale independent and analytical way. In this paper we summarize recent results for the finite-mass fermionic corrections to the heavy quark potential through two loops leading to the numerical solution of the physical and mass dependent Gell-Mann Low function. The decoupling-, massless- and Abelian-limits are reproduced and an analytical fitting function is obtained in the V-scheme. Thus the gauge invariant mass dependence of $α_V$ is now known through two loops. Possible applications in lattice analyses, heavy quark physics and effective charges are briefly discussed.

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Michael Melles. 1999-07-18. Exact gauge invariant mass dependence of α_s through two loops. https://doi.org/10.1016/s0920-5632(00)00566-1

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