On the precision of a data-driven estimate of the pseudoscalar-pole contribution to hadronic light-by-light scattering in the muon g−2

Abstract

The evaluation of the numerically dominant pseudoscalar-pole contribution to hadronic light-bylight scattering in the muon g − 2 involves the pseudoscalar-photon transition form factor FPγ*γ*(−Q12−Q22) with P = π0, η, η′ and, in general, two off-shell photons with spacelike momenta Q1,22. We determine which regions of photon momenta give the main contribution for hadronic light-by-light scattering. Furthermore, we analyze how the precision of future measurements of the single- and double-virtual form factor impacts the precision of a data-driven estimate of this contribution to hadronic light-by-light scattering.