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arXiv · hep-ph/9812277

Semi-Exclusive Processes: New Probes of Hadron Structure

S. J. Brodsky·M. Diehl·P. Hoyer·S. Peigne
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Abstract

We define and study hard ``semi-exclusive'' processes of the form $A+B \to C + Y$ which are characterized by a large momentum transfer between the particles $A$ and $C$ and a large rapidity gap between the final state particle $C$ and the inclusive system $Y$. Such reactions are in effect generalizations of deep inelastic lepton scattering, providing novel currents which probe specific quark distributions of the target $B$ at fixed momentum fraction. We give explicit expressions for photo- and leptoproduction cross sections such as $γp \to πY$ in terms of parton distributions in the proton and the pion distribution amplitude. Semi-exclusive processes provide opportunities to study fundamental issues in QCD, including odderon exchange and color transparency, and suggest new ways to measure spin-dependent parton distributions.

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S. J. Brodsky, M. Diehl, P. Hoyer, S. Peigne. 1998-12-08. Semi-Exclusive Processes: New Probes of Hadron Structure. https://doi.org/10.1016/s0370-2693(99)00082-9

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