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arXiv · 2112.03586

Pion-pole contribution to HLbL from twisted mass lattice QCD at the physical point

Sebastian Burri·Constantia Alexandrou·Simone Bacchio·Georg Bergner·Jacob Finkenrath·Andrew Gasbarro·Kyriakos Hadjiyiannakou·Karl Jansen·Bartosz Kostrzewa·Giannis Koutsou·Konstantin Ottnad·Marcus Petschlies·Ferenc Pittler·Fernanda Steffens·Carsten Urbach·Urs Wenger
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Abstract

We report on our computation of the pion transition form factor ${\cal F}_{P\rightarrow \gamma^*\gamma^*}$ from twisted mass lattice QCD in order to determine the numerically dominant light pseudoscalar pole contribution in the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon $a_\mu =(g-2)_\mu$. The pion transition form factor is computed directly at the physical point. We present first results for our estimate of the pion-pole contribution with kinematic setup for the pion at rest.

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Sebastian Burri, Constantia Alexandrou, Simone Bacchio, Georg Bergner, Jacob Finkenrath, Andrew Gasbarro, Kyriakos Hadjiyiannakou, Karl Jansen, Bartosz Kostrzewa, Giannis Koutsou, Konstantin Ottnad, Marcus Petschlies, Ferenc Pittler, Fernanda Steffens, Carsten Urbach, Urs Wenger. 2021-12-07. Pion-pole contribution to HLbL from twisted mass lattice QCD at the physical point. https://doi.org/10.22323/1.396.0519

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