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arXiv · 1801.04238

Hadronic light-by-light scattering contribution to the muon g-2 on the lattice

Nils Asmussen·Antoine Gerardin·Jeremy Green·Oleksii Gryniuk·Georg von Hippel·Harvey B. Meyer·Andreas Nyffeler·Vladimir Pascalutsa·Hartmut Wittig
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Abstract

We briefly review several activities at Mainz related to hadronic light-by-light scattering (HLbL) using lattice QCD. First we present a position-space approach to the HLbL contribution in the muon g-2, where we focus on exploratory studies of the pion-pole contribution in a simple model and the lepton loop in QED in the continuum and in infinite volume. The second part describes a lattice calculation of the double-virtual pion transition form factor F_{pi^0 gamma^* gamma^*}(q_1^2, q_2^2) in the spacelike region with photon virtualities up to 1.5 GeV^2 which paves the way for a lattice calculation of the pion-pole contribution to HLbL. The third topic involves HLbL forward scattering amplitudes calculated in lattice QCD which can be described, using dispersion relations (HLbL sum rules), by gamma^* gamma^* -> hadrons fusion cross sections and then compared with phenomenological models.

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Nils Asmussen, Antoine Gerardin, Jeremy Green, Oleksii Gryniuk, Georg von Hippel, Harvey B. Meyer, Andreas Nyffeler, Vladimir Pascalutsa, Hartmut Wittig. 2018-01-12. Hadronic light-by-light scattering contribution to the muon g-2 on the lattice. https://doi.org/10.1051/epjconf/201817901017

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