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arXiv · 1402.7081

Dispersive approach to hadronic light-by-light scattering

Gilberto Colangelo·Martin Hoferichter·Massimiliano Procura·Peter Stoffer
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Abstract

Based on dispersion theory, we present a formalism for a model-independent evaluation of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon. In particular, we comment on the definition of the pion pole in this framework and provide a master formula that relates the effect from pi pi intermediate states to the partial waves for the process gamma^* gamma^* --> pi pi. All contributions are expressed in terms of on-shell form factors and scattering amplitudes, and as such amenable to an experimental determination.

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Gilberto Colangelo, Martin Hoferichter, Massimiliano Procura, Peter Stoffer. 2014-08-22. Dispersive approach to hadronic light-by-light scattering. https://doi.org/10.1007/jhep09(2014)091

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