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arXiv · hep-ph/0507278

Running couplings for the simultaneous decoupling of heavy quarks

Steven D. Bass·R. J. Crewther·F. M. Steffens·A. W. Thomas
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Abstract

Scale-invariant running couplings are constructed for several quarks being decoupled together, without reference to intermediate thresholds. Large-momentum scales can also be included. The result is a multi-scale generalization of the renormalization group applicable to any order. Inconsistencies in the usual decoupling procedure with a single running coupling can then be avoided, e.g. when cancelling anomalous corrections from t,b quarks to the axial charge of the proton.

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Steven D. Bass, R. J. Crewther, F. M. Steffens, A. W. Thomas. 2006-01-24. Running couplings for the simultaneous decoupling of heavy quarks. https://doi.org/10.1016/j.physletb.2006.01.064

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