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arXiv · 1510.08384

Direct calculation of hadronic light-by-light scattering

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

We report calculations of hadronic light-by-light scattering amplitudes via lattice QCD evaluation of Euclidean four-point functions of vector currents. These initial results include only the fully quark-connected contribution. Particular attention is given to the case of forward scattering, which can be related via dispersion relations to the $γ^* γ^* \to$ hadrons cross section, and thus allows lattice data to be compared with phenomenology. We also present a strategy for computing the hadronic light-by-light contribution to the muon anomalous magnetic moment.

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Jeremy Green, Nils Asmussen, Oleksii Gryniuk, Georg von Hippel, Harvey B. Meyer, Andreas Nyffeler, Vladimir Pascalutsa. 2015-10-28. Direct calculation of hadronic light-by-light scattering. https://arxiv.org/abs/1510.08384

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