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arXiv · 2005.14047

Matching the heavy-quark fields in QCD and HQET at four loops

Andrey G. Grozin·Peter Marquard·Alexander V. Smirnov·Vladimir A. Smirnov·Matthias Steinhauser
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Abstract

The QCD/HQET matching coefficient for the heavy-quark field is calculated up to four loops. It must be finite; this requirement produces analytical results for some terms in the four-loop on-shell heavy-quark field renormalization constant which were previously only known numerically. The effect of a non-zero lighter-flavor mass is calculated up to three loops. A class of on-shell integrals with two masses is analyzed in detail. By specifying our result to QED, we obtain the relation between the electron field and the Bloch--Nordsieck field with four-loop accuracy.

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Andrey G. Grozin, Peter Marquard, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser. 2020-05-28. Matching the heavy-quark fields in QCD and HQET at four loops. https://doi.org/10.1103/physrevd.102.054008

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