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2-loop short-distance constraints for the g − 2 HLbL

Bijnens, Johan LU orcid ; Hermansson-Truedsson, Nils ; Laub, Laetitia and Rodríguez-Sánchez, Antonio (2022) In Nuclear and Particle Physics Proceedings 318-323. p.182-186
Abstract

The recent experimental measurement of the muon g−2 at Fermilab National Laboratory, at a 4.2σ tension with the Standard Model prediction, highlights the need for further improvements on the theoretical uncertainties associated to the hadronic sector. In the framework of the operator product expansion in the presence of a background feld, the short-distance behaviour of the hadronic light-by-light contribution was recently studied. The leading term in this expansion is given by the massless quark-loop, which is numerically dominant compared to non-perturbative corrections. Here, we present the perturbative QCD correction to the massless quark-loop and estimate its size numerically. In particular, we fnd that for scales above 1 GeV it is... (More)

The recent experimental measurement of the muon g−2 at Fermilab National Laboratory, at a 4.2σ tension with the Standard Model prediction, highlights the need for further improvements on the theoretical uncertainties associated to the hadronic sector. In the framework of the operator product expansion in the presence of a background feld, the short-distance behaviour of the hadronic light-by-light contribution was recently studied. The leading term in this expansion is given by the massless quark-loop, which is numerically dominant compared to non-perturbative corrections. Here, we present the perturbative QCD correction to the massless quark-loop and estimate its size numerically. In particular, we fnd that for scales above 1 GeV it is relatively small, in general roughly −10% the size of the massless quark-loop. The knowledge of these short-distance constraints will in the future allow to reduce the systematic uncertainties in the Standard Model prediction of the hadronic light-by-light contribution to the g−2.

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author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Higher Order Calculations, Muon Anomalous Magnetic Moment, Operator Product Expansion, Short-distance Constraints, Standard Model Tests
in
Nuclear and Particle Physics Proceedings
volume
318-323
pages
5 pages
publisher
Elsevier
external identifiers
  • scopus:85142186474
ISSN
2405-6014
DOI
10.1016/j.nuclphysbps.2022.09.035
language
English
LU publication?
yes
id
fa6646cc-9fcd-4723-82ad-e84210660c46
date added to LUP
2022-12-28 09:18:09
date last changed
2024-04-04 17:04:24
@article{fa6646cc-9fcd-4723-82ad-e84210660c46,
  abstract     = {{<p>The recent experimental measurement of the muon g−2 at Fermilab National Laboratory, at a 4.2σ tension with the Standard Model prediction, highlights the need for further improvements on the theoretical uncertainties associated to the hadronic sector. In the framework of the operator product expansion in the presence of a background feld, the short-distance behaviour of the hadronic light-by-light contribution was recently studied. The leading term in this expansion is given by the massless quark-loop, which is numerically dominant compared to non-perturbative corrections. Here, we present the perturbative QCD correction to the massless quark-loop and estimate its size numerically. In particular, we fnd that for scales above 1 GeV it is relatively small, in general roughly −10% the size of the massless quark-loop. The knowledge of these short-distance constraints will in the future allow to reduce the systematic uncertainties in the Standard Model prediction of the hadronic light-by-light contribution to the g−2.</p>}},
  author       = {{Bijnens, Johan and Hermansson-Truedsson, Nils and Laub, Laetitia and Rodríguez-Sánchez, Antonio}},
  issn         = {{2405-6014}},
  keywords     = {{Higher Order Calculations; Muon Anomalous Magnetic Moment; Operator Product Expansion; Short-distance Constraints; Standard Model Tests}},
  language     = {{eng}},
  pages        = {{182--186}},
  publisher    = {{Elsevier}},
  series       = {{Nuclear and Particle Physics Proceedings}},
  title        = {{2-loop short-distance constraints for the g − 2 HLbL}},
  url          = {{http://dx.doi.org/10.1016/j.nuclphysbps.2022.09.035}},
  doi          = {{10.1016/j.nuclphysbps.2022.09.035}},
  volume       = {{318-323}},
  year         = {{2022}},
}