Short-distance HLbL contributions to the muon g-2

Summary, in English

The current 3.7σ discrepancy between the Standard Model prediction and the experimental value of the muon anomalous magnetic moment could be a hint for the existence of new physics. The hadronic light-by-light contribution is one of the pieces requiring improved precision on the theory side, and an important step is to derive short-distance constraints for this quantity containing four electromagnetic currents. Here, we derive such short-distance constraints for three large photon loop virtualities and the external fourth photon in the static limit. The static photon is considered as a background field and we construct a systematic operator product expansion in the presence of this field. We show that the massless quark loop, i.e. the leading term, is numerically dominant over non-perturbative contributions up to next-to-next-to leading order, both those suppressed by quark masses and those that are not.

• Author: Johan Bijnens; Nils Hermansson-Truedsson; Laetitia Laub; Antonio Rodríguez-Sánchez
• Department/s: Theoretical Particle Physics - Has been reorganised
• Publishing year: 2021-07
• Language: English
• Pages: 180-184
• Publication/Series: Nuclear and Particle Physics Proceedings
• Volume: 312-317
• Links: http://dx.doi.org/10.1016/j.nuclphysbps.2021.05.048
• Document type: Journal article
• Publisher: Elsevier
• Topic: Subatomic Physics
• Keywords: g-2; Hadronic Light-by-Light; HLbL; Muon Anomalous Magnetic Moment; Non-Perturbative Contributions; Operator Product Expansion; Short-Distance Constraints
• Status: Published
• ISBN/ISSN/Other: ISSN: 2405-6014