Short-distance constraints for the HLbL contribution to the muon anomalous magnetic moment

Summary, in English

We derive short-distance constraints for the hadronic light-by-light contribution (HLbL) to the anomalous magnetic moment of the muon in the kinematic region where the three virtual momenta are all large. We include the external soft photon via an external field leading to a well-defined Operator Product Expansion. We establish that the perturbative quark loop gives the leading contribution in a well defined expansion. We compute the first nonzero power correction. It is related to to the magnetic susceptibility of the QCD vacuum. The results can be used as model-independent short-distance constraints for the very many different approaches to the HLbL contribution. Numerically the power correction is found to be small.

• Author: Nils Hermansson Truedsson; Johan Bijnens; Antonio Rodríguez Sánchez
• Department/s: Theoretical Particle Physics - Has been reorganised
• Publishing year: 2019-11-10
• Language: English
• Publication/Series: Physics Letters B
• Volume: 798
• Links: https://arxiv.org/pdf/1908.03331.pdf; http://dx.doi.org/10.1016/j.physletb.2019.134994
• Document type: Journal article
• Publisher: Elsevier
• Topic: Subatomic Physics
• Status: Published
• Project: Higher Order Calculations for Low Energy Precision Physics
• ISBN/ISSN/Other: ISSN: 0370-2693