Deeply Virtual Compton Scattering at HERA II (H1 results)

Abstract

New results on the Deeply Virtual Compton Scattering process $\gamma^* p \to \gamma p$ (DVCS) from H1 experiment at the $e p$ collider HERA are presented, using data collected during the year 2004 and corresponding to an integrated luminosity of 39.7 pb$^{-1}$. The DVCS cross section is measured as a function of the photon virtuality, $Q^2$, the $\gamma^* p $ c.m.s. energy $W$ and differentially in the momentum transfer squared at the proton vertex, $t$, in the kinematic range $6.5 < Q^2 < 80 $ GeV$^2$, $30 < W < 140$ GeV and $|t| < 1$ GeV$^2$. The results are found to be in good agreement with the published H1 and ZEUS measurements and compared to NLO QCD calculations based on Generalized Parton Distributions (GPD) and to predictions from Color Dipole Model.