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arXiv · hep-ph/9701415

HQET chromomagnetic interaction at two loops

A. Czarnecki·A. G. Grozin
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Abstract

We present the coefficient of the chromomagnetic interaction operator, the only unknown coefficient in the Heavy Quark Effective Theory (HQET) lagrangian up to the $1/m$ level, with the two-loop accuracy by matching scattering amplitudes of an on-shell heavy quark in an external field in full QCD and HQET, and obtain the two-loop anomalous dimension of this operator in HQET.

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A. Czarnecki, A. G. Grozin. 1997-04-29. HQET chromomagnetic interaction at two loops. https://doi.org/10.1016/s0370-2693(97)00587-x%2010.1016%2Fj.physletb.2007.05.016

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