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arXiv · hep-ph/0701243

Pion-photon Transition Distribution Amplitudes in the Spectral Quark Model

Abstract

The vector and axial pion-photon transition distribution amplitudes are analyzed in the Spectral Quark Model. We proceed by the evaluation of double distributions through the use of a manifestly covariant calculation based on the alpha representation of propagators. As a result polynomiality is incorporated and calculations become rather simple. Explicit formulas, holding at the low-energy quark-model scale, are obtained. The corresponding form factors for the anomalous decay pi0 -> gamma gamma* and the radiative pion decays are also evaluated and confronted with the data.

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Wojciech Broniowski, Enrique Ruiz Arriola. 2007-03-01. Pion-photon Transition Distribution Amplitudes in the Spectral Quark Model. https://doi.org/10.1016/j.physletb.2007.03.047

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