English

Pseudoscalar-pole contributions to the muon $g-2$ at the physical point

High Energy Physics - Lattice 2022-12-21 v1

Abstract

Pseudoscalar-pole diagrams are an important component of estimates of the hadronic light-by-light (HLbL) contribution to the muon g2g-2. We report on our computation of the transition form factors FPγγ\mathcal{F}_{P \rightarrow \gamma^* \gamma^*} for the neutral pseudoscalar mesons P=π0P=\pi^0 and η\eta. The calculation is performed using twisted-mass lattice QCD with physical quark masses. On the lattice, we have access to a broad range of (space-like) photon four-momenta and therefore produce form factor data complementary to the experimentally accessible single-virtual direction, which directly leads to an estimate of the pion- and η\eta-pole components of the muon g2g-2. For the pion, our result for the g2g-2 contribution in the continuum is comparable with previous lattice and data-driven determinations, with combined relative uncertainties below 10%10\%. For the η\eta meson, we report on a preliminary determination from a single lattice spacing.

Keywords

Cite

@article{arxiv.2212.10300,
  title  = {Pseudoscalar-pole contributions to the muon $g-2$ at the physical point},
  author = {Sebastian Burri and Gurtej Kanwar and Constantia Alexandrou and Simone Bacchio and Georg Bergner and Jacob Finkenrath and Andrew Gasbarro and Kyriakos Hadjiyiannakou and Karl Jansen and Bartosz Kostrzewa and Giannis Koutsou and Konstantin Ottnad and Marcus Petschlies and Ferenc Pittler and Fernanda Steffens and Carsten Urbach and Urs Wenger},
  journal= {arXiv preprint arXiv:2212.10300},
  year   = {2022}
}