Running couplings for the simultaneous decoupling of heavy quarks

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.

12 pages, 1 figure, version to appear in PLB. Pages 8-11 and Fig. 1 are new, with consequent changes to the abstract, page 2, and the references. We show that our multi-scale renormalization group is needed to achieve anomaly cancellation in t,b decoupling from the weak neutral current, and extend it to include large momenta

References in corpus (4)

• The Spin Structure of the Proton
• Next-to-leading mass singularities in two-loop electroweak singlet form factors
• Physical Renormalization Schemes and Grand Unification
• Decoupling heavy particles simultaneously

Cited by in corpus (2)

• Review of two-photon exchange in electron scattering
• Bottom quark contribution to spin-dependent dark matter detection