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arXiv · 1812.09307

Probing Generalized Parton Distributions through the photoproduction of a $\gamma \pi$ pair

G. Duplančić·K. Passek-Kumerički·B. Pire·L. Szymanowski·S. Wallon
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Abstract

We study in the framework of collinear QCD factorization the photoproduction of a $\gamma\,\pi$ pair with a large invariant mass and a small transverse momentum, as a new way to access generalized parton distributions. In the kinematics of JLab 12-GeV, we demonstrate the feasibility of this measurement and show the extreme sensitivity of the unpolarized cross section to the axial quark GPDs.

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G. Duplančić, K. Passek-Kumerički, B. Pire, L. Szymanowski, S. Wallon. 2018-12-21. Probing Generalized Parton Distributions through the photoproduction of a $\gamma \pi$ pair. https://arxiv.org/abs/1812.09307

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