arXiv:hep-ph/0604072·v1·High Energy Physics — Phenomenology
Two-Loop Matching Coefficients for Heavy Quark Currents
B.A. Kniehl🇩🇪 · A. Onishchenko🇩🇪 · J.H. Piclum🇩🇪 · M. Steinhauser🇩🇪
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.
Comments: 9 pages