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arXiv · 1708.09164

Exploring GPDs through the photoproduction of a $γρ$ pair

R. Boussarie·B. Pire·L. Szymanowski·S. Wallon
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Abstract

We describe the process $γN \to γ\,ρN'$ in the generalized Bjorken regime where the $γ\,ρ$ pair has a large invariant mass. In the collinear QCD factorization framework, the amplitude gives access to both chiral-even and chiral-odd quark generalized parton distributions (GPDs), and is insensitive to gluon GPDs. The separation of longitudinally and transversely polarized $ρ$ meson production allows to distinguish chiral-even and chiral-odd contributions. Production rates are estimated in the kinematics of the near-future JLab~12-GeV experiments.

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R. Boussarie, B. Pire, L. Szymanowski, S. Wallon. 2017-08-30. Exploring GPDs through the photoproduction of a $γρ$ pair. https://arxiv.org/abs/1708.09164

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