Testing the handbag contribution to exclusive virtual Compton scattering

Abstract

We discuss the handbag approximation to exclusive deep virtual Compton scattering. After defining the kinematical region where this approximation can be valid, we propose tests for its relevance in planned electroproduction experiments, e + p -> e + p + gamma. We focus on scaling laws in the cross section, and the distribution in the angle between the lepton and hadron planes, which contains valuable information on the angular momentum structure of the Compton process. We advocate to measure weighted cross sections, which make use of the data in the full range of this angle and do not require very high event statistics.

Figures (3)

• Figure 1: The handbag Born diagrams for virtual Compton scattering. Here $x$ and $x'$ are light cone fractions of the quark with respect to the incoming proton momentum.
• Figure 2: The Bethe-Heitler process.
• Figure 3: Kinematics of reaction (\ref{['ep']}) in the c.m. of the scattered photon and proton.