Your browser has javascript turned off or blocked. This will lead to some parts of our website to not work properly or at all. Turn on javascript for best performance.

The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Photo of Johan Bijnens

Johan Bijnens

Professor

Photo of Johan Bijnens

Electromagnetic finite-size effects to the hadronic vacuum polarization

Author

  • Johan Bijnens
  • James Harrison
  • Nils Hermansson Truedsson
  • Tadeusz Janowski
  • Andreas Juettner
  • Antonin Portelli

Summary, in English

In order to reduce the current hadronic uncertainties in the theory prediction for the anomalous magnetic moment of the muon, lattice calculations need to reach subpercent accuracy on the hadronic-vacuum-polarization contribution. This requires the inclusion of O(α) electromagnetic corrections. The inclusion of electromagnetic interactions in lattice simulations is known to generate potentially large finite-size effects suppressed only by powers of the inverse spatial extent. In this paper we derive an analytic expression for the QEDL finite-volume corrections to the two-pion contribution to the hadronic vacuum polarization at next-to-leading order in the electromagnetic coupling in scalar QED. The leading term is found to be of order 1/L3 where L is the spatial extent. A 1/L2 term is absent since the current is neutral and a photon far away thus sees no charge and we show that this result is universal. Our analytical results agree with results from the numerical evaluation of loop integrals as well as simulations of lattice scalar U(1) gauge theory with stochastically generated photon fields. In the latter case the agreement is up to exponentially suppressed finite-volume effects. For completeness we also calculate the hadronic vacuum polarization in infinite volume using a basis of 2-loop master integrals.

Department/s

  • Theoretical Particle Physics

Publishing year

2019

Language

English

Publication/Series

Physical Review D - Particles, Fields, Gravitation and Cosmology

Volume

100

Issue

1

Document type

Journal article

Publisher

American Physical Society

Topic

  • Subatomic Physics

Status

Published

Project

  • Higher Order Calculations for Low Energy Precision Physics

ISBN/ISSN/Other

  • ISSN: 2470-0010