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Electromagnetic corrections to gamma pi(+) -> pi(0) pi(+)

Ll. Ametller·M. Knecht·P. Talavera
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Abstract

The amplitude for the anomalous transitions gamma pi(+) -> pi(0) pi(+) is analyzed within Chiral Perturbation Theory including electromagnetic interactions. The presence of a t-channel one-photon exchange contribution induces sizeable e^2 corrections which enhance the cross-section in the threshold region and bring the theoretical prediction into agreement with available data. In the case of the crossed reaction gamma pi(0) -> pi(+) pi(-), the same contribution appears in the s-channel and its effects are small.

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Ll. Ametller, M. Knecht, P. Talavera. 2001-09-19. Electromagnetic corrections to gamma pi(+) -> pi(0) pi(+). https://doi.org/10.1103/physrevd.64.094009

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