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arXiv · 2203.11231

Three-loop non-singlet matching coefficients for heavy quark currents

Manuel Egner·Matteo Fael·Fabian Lange·Kay Schönwald·Matthias Steinhauser
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Abstract

We compute the matching coefficients between QCD and non-relativistic QCD for external vector, axial-vector, scalar and pseudo-scalar currents up to three-loop order. We concentrate on the non-singlet contributions and present precise numerical results with an accuracy of about ten digits. For the vector current the results from arXiv:1401.3004 are confirmed, increasing the accuracy by several orders of magnitude.

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Manuel Egner, Matteo Fael, Fabian Lange, Kay Schönwald, Matthias Steinhauser. 2022-03-21. Three-loop non-singlet matching coefficients for heavy quark currents. https://doi.org/10.1103/physrevd.105.114007

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