Running couplings for the simultaneous decoupling of heavy quarks
نویسنده
چکیده
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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