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arXiv · 1409.2174

Lightest pseudoscalar exchange contribution to light-by-light scattering piece of the muon g-2

Pablo Roig·Adolfo Guevara·Gabriel López Castro
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Abstract

Lightest pseudoscalar (P= pi^0, eta, eta') exchange contribution to the light-by-light (LbL) scattering piece of the muon anomaly, a_mu=(g_mu-2)/2, has been evaluated using a resonance chiral Lagrangian (R\chi L). Best description of pion transition form-factor (TFF) data is obtained with only tiny violations of one of the relations in the minimal consistent set of short-distance constraints on the anomalous R\chi L couplings. eta^{(')} TFF, predicted in terms of the pi TFF and the eta-eta^' mixing, are in good agreement with measurements. With this input, we obtain a_mu^{P,LbL} = (10.47\pm0.54)x10^-10, consistent with the reference determinations in the literature, albeit with smaller error.

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Pablo Roig, Adolfo Guevara, Gabriel López Castro. 2014-09-07. Lightest pseudoscalar exchange contribution to light-by-light scattering piece of the muon g-2. https://arxiv.org/abs/1409.2174

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