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arXiv · 0812.3329

Distribution amplitude for the photon-pion transition

A. Courtoy·S. Noguera
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Abstract

The exclusive production of ππand πρin hard γ^{\star}γscattering in the forward kinematical region where the virtual photon is highly off-shell are studied through the γ\toπ^- Transition Distribution Amplitudes. The calculation is based on a covariant Bethe-Salpeter approach, applied to the Nambu - Jona-Lasinio model, for the determination of the pion bound state. In particular it is shown that the pion pole contribution produces a large enhancement of the differential cross section for the pion pair production with respect to previous estimates.

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A. Courtoy, S. Noguera. 2008-12-17. Distribution amplitude for the photon-pion transition. https://arxiv.org/abs/0812.3329

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