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Two-Loop Matching Coefficients for Heavy Quark Currents

B. A. Kniehl·A. Onishchenko·J. H. Piclum·M. Steinhauser
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Abstract

In this paper we consider the matching coefficients up to two loops between Quantum Chromodynamics (QCD) and Non-Relativistic QCD (NRQCD) for the vector, axial-vector, scalar and pseudo-scalar currents. The structure of the effective theory is discussed and analytical results are presented. Particular emphasis is put on the singlet diagrams.

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B. A. Kniehl, A. Onishchenko, J. H. Piclum, M. Steinhauser. 2006-04-07. Two-Loop Matching Coefficients for Heavy Quark Currents. https://doi.org/10.1016/j.physletb.2006.05.023

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