Measurement of deeply virtual Compton scattering at HERA

Abstract

The cross-section for deeply virtual Compton scattering in the reaction ep → eγp has been measured with the ZEUS detector at HERA using integrated luminosities of 95.0 pb −1 of e + p and 16.7 pb −1 of e − p collisions. Differential cross-sections are presented as a function of the exchanged-photon virtuality, Q 2 , and the centre-of-mass energy, W , of the γ ∗ p system in the region 5< Q 2 <100 GeV 2 and 40< W <140 GeV. The measured cross-sections rise steeply with increasing  W . The measurements are compared to QCD-based calculations