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The experimental challenge of virtual compton scattering above 8 GeV

P. Y. Bertin·Y. Roblin·C. E. Hyde-Wright
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Abstract

We discuss the experimental issues confronting measurements of the Virtual Compton Scattering (VCS) reaction ep->ep gamma with electron beam energies 6-30 GeV. We specifically address the kinematics of Deeply Virtual Compton Scattering (Deep Inelastic Scattering, with coincident detection of the exclusive real photon nearly parallel to the virtual photon direction) and large transverse momentum VCS (High energy VCS of arbitrary Q**2, and the recoil proton emitted with high momentum transverse to the virtual photon direction). We discuss the experimental equipment necessary for these measurements. For the DVCS, we emphasize the importance of the Bethe-Heitler-Compton interference terms that can be measured with the electron-positron (beam charge) asymmetry, and the electron beam helicity asymmetry.

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P. Y. Bertin, Y. Roblin, C. E. Hyde-Wright. 1999-10-18. The experimental challenge of virtual compton scattering above 8 GeV. https://arxiv.org/abs/hep-ph/9910381

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