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arXiv · 1007.2710

Photoproduction of a πρPair and Transversity GPDs

M. El Beiyad·B. Pire·L. Szymanowski·S. Wallon
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Abstract

We demonstrate that the chiral-odd transversity generalized parton distributions (GPDs) of the nucleon can be accessed through the exclusive photoproduction process gamma + N -> pi + rho + N', in the kinematics where the meson pair has a large invariant mass and the final nucleon has a small transverse momentum, provided the vector meson is produced in a transversely polarized state. We calculate perturbatively the scattering amplitude at leading order in alpha_s: We build a simple model for the dominant transversity GPD HT (x; chi; t) based on the concept of double distribution. Counting rates estimates show that the experiment looks feasible with the real photon beam characteristics expected at JLab@12 GeV, in low Q2 leptoproduction at Jlab@12 GeV and in the COMPASS experiment.

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M. El Beiyad, B. Pire, L. Szymanowski, S. Wallon. 2010-07-16. Photoproduction of a πρPair and Transversity GPDs. https://doi.org/10.1142/9789814329569_0040

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