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Hadronic light-by-light scattering contribution to the muon g-2: an effective field theory approach

M. Knecht·A. Nyffeler·M. Perrottet·E. de Rafael
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Abstract

The hadronic light-by-light contribution to a_{mu}, the anomalous magnetic moment of the muon, is discussed from the point of view of an effective low-energy theory. As an application, the coefficient of the leading logarithm arising from the two-loop graphs involving two anomalous vertices is computed, and found to be positive. This corresponds to a positive sign for the pion-pole contribution to the hadronic light-by-light correction to a_{mu}, and to a sizeable reduction of the discrepancy between the present experimental value of a_{mu} and its theoretical counterpart in the standard model.

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M. Knecht, A. Nyffeler, M. Perrottet, E. de Rafael. 2002-02-18. Hadronic light-by-light scattering contribution to the muon g-2: an effective field theory approach. https://doi.org/10.1103/physrevlett.88.071802

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