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arXiv · 1011.3410

Hard exclusive processes in the backward region

J. P. Lansberg·B. Pire·L. Szymanowski
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Abstract

We review the potentialities offered by the study of backward exclusive processes in a new scaling regime, i.e. involving a large -timelike or spacelike- Q2 photon and a baryonic exchange in the t-channel. We recall the concept of Transition Distribution Amplitudes (TDAs) containing unique information on the hadron structure, then discuss how they enter the description of processes such as backward electroproduction of a pion, antiproton-proton annihilations into a dilepton + meson as well as into J/psi + meson. We then discuss first phenomenological studies for processes that are being analysed at JLAB and HERMES or that will be measured by Panda at GSI-FAIR. Finally we present outlooks for their theoretical studies based on approaches such as the pion-cloud model.

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J. P. Lansberg, B. Pire, L. Szymanowski. 2010-11-15. Hard exclusive processes in the backward region. https://arxiv.org/abs/1011.3410

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