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arXiv · hep-ph/9305305

QCD Matching Conditions at Thresholds

German Rodrigo·Arcadi Santamaria
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Abstract

The use of MS-like renormalization schemes in QCD requires an implementation of nontrivial matching conditions across thresholds, a fact often overlooked in the literature. We shortly review the use of these matching conditions in QCD and check explicitly that the prediction for $α_s(M_Z)$, obtained by running the strong coupling constant from the $M_τ$ scale, does not substantially depend on the exact value of the matching point chosen in crossing the $b$-quark threshold when the appropriate matching conditions are taken into account.

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German Rodrigo, Arcadi Santamaria. 1993-05-24. QCD Matching Conditions at Thresholds. https://doi.org/10.1016/0370-2693(93)90016-b

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