Pion-photon Transition Distribution Amplitudes in the Spectral Quark Model ⋆
نویسندگان
چکیده
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 α 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 π0 → γγ and the radiative pion decays π → lνlγ are also evaluated and confronted with the data.
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