We present the first measurements of the e⃗p→epγ cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q2 dependence (from 1.5 to 2.3 GeV2) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q2. The helicity-independent cross section is also measured at Q2=2.3 GeV2. We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation.
Camacho, C. Muñoz; Holmstrom, Timothy; and Jefferson Lab Hall A Collaboration, "Scaling Tests of the Cross Section for Deeply Virtual Compton Scattering" (2006). Chemistry and Physics Faculty Publications. 11.
Phys. Rev. Lett. 97, 262002 (2006)