Related papers: Testing the handbag contribution to exclusive virt…
We investigate the exclusive photoproduction of a heavy timelike photon which decays into a lepton pair, gamma p -> l+ l- p. This can be seen as the analog of deeply virtual Compton scattering, and we argue that the two processes are…
The Deeply Virtual Compton Scattering (DVCS) $\gamma^* p \to \gamma p$ cross section has been measured with the H1 detector at HERA with an increased precision and in an extended kinematic domain: at photon virtualities $4<Q^2<80$ GeV$^2$,…
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…
We systematically evaluate observables for hard exclusive electroproduction of real photons and compare them to experiment using a set of Generalized Parton Distributions (GPDs) whose parameters are constrained by Deeply Virtual Meson…
Using the helicity amplitudes formalism, we study deeply virtual exclusive electron photo-production off an unpolarized nucleon target, $ep \rightarrow e' p' \gamma$, through a range of kinematics both in the fixed target setting with…
We propose measurements of the deeply virtual Compton amplitude (DVCS), gamma* to H H-bar gamma, in the timelike t = (p_{H} + p_{H-bar})^2 > 0 kinematic domain which is accessible at electron-positron colliders via the radiative…
We propose precision measurements of the helicity-dependent and helicity independent cross sections for the ep->epg reaction in Deeply Virtual Compton Scattering (DVCS) kinematics. DVCS scaling is obtained in the limits Q^2>>Lambda_{QCD}^2,…
We calculate polarization phenomena for virtual Compton scattering on protons, at relatively large momentum transfer 1 GeV$^2$ $\le -q^2\le$ 5 GeV$^2$ on the basis of a model for $\gamma^*+ p\to \gamma+p$ with two main contributions:…
Deeply Virtual Compton Scattering in the near forward kinematic region is the golden access to Generalized Parton Distributions. We studied the O(alphaS) corrections to the scattering amplitude for both spacelike and timelike kinematics…
Deeply virtual Compton scattering has been measured in e^+p collisions at HERA with the ZEUS detector using an integrated luminosity of 61.1 pb^-1. Cross sections are presented as a function of the photon virtuality, Q^2, and photon-proton…
Cross-section values for Compton scattering on the proton were measured at 25 kinematic settings over the range s = 5-11 and -t = 2-7 GeV2 with statistical accuracy of a few percent. The scaling power for the s-dependence of the cross…
Deeply virtual Compton scattering has recently been studied by three HERA experiments, H1, ZEUS and HERMES, covering a broad range of kinematic regimes. We present cross section measurements of the two collider experiments in the kinematic…
The hard exclusive electroproduction processes provide new information about hadronic structure accumulated in nonforward parton distributions. The NFPD's are universal hybrid functions having the properties of parton densities, hadronic…
We study deeply virtual Compton scattering (DVCS) on a deuteron target. We model the Generalized Quark Distributions in the deuteron by using the impulse approximation for the lowest Fock-space state. Numerical predictions are given for the…
We study the kinematics and cross section of the scattering process $e p \rightarrow e \Sigma^+$. The cross section is expressed in terms of complex form factors characterizing the hadron vertices. We estimate the cross section for small…
Poincare invariance, gauge invariance, conservation of parity and time reversal invariance are respected in an impulse approximation evaluation of the handbag diagram. Proton wave functions, previously constrained by comparison with…
We study Compton scattering, gamma e -> gamma e, in the context of the recent proposal for Weak Scale Quantum Gravity (WSQG) with large extra dimensions. It is shown that, with an ultraviolet cutoff $M_S \sim 1$ TeV for the effective…
The process of deeply virtual Compton scattering will be shortly introduced, and the latest results from measurements at the HERA ep-collider at DESY will be given. In particular, the cross section has been measured with increased…
Virtual Compton Scattering off the proton: gamma* p to gamma p, is a new field of investigation of nucleon structure. Several dedicated experiments have been performed at low c.m. energy and various momentum transfers, yielding specific…
Real and virtual Compton scattering has been and will be an important tool to study the structure of hadronic systems. We summarize the status of real Compton scattering and give an outlook at the new theoretical and experimental…