Related papers: Exclusive Hard Diffraction at HERA (DVCS and Vecto…
A new measurement is presented of elastic deeply virtual Compton scattering (DVCS) based on data taken by the H1 detector during the complete HERA II period. The data are well described by QCD based calculations. For the first time, a beam…
Deeply Virtual Compton Scattering (DVCS) in $ep$ collisions has emerged in recent years as a an essential reaction to obtain information on the correlation of partons in the hadron (proton) or on the transverse distribution of these…
Experimental results from HERA on diffractive vector meson production and their theoretical interpretation within microscopic QCD are reviewed with an emphasis on the BFKL color dipole and kt-factorization approaches.
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 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$^2$,…
Exclusive vector meson production from real and virtual photons is, for the most part, described well by soft pomeron exchange. However, there are some unsolved normalisation problems, and just a hint that an additional contribution from…
Recent results on diffraction at HERA, from the H1 and ZEUS Collaborations, and at Tevatron, from the CDF and D0 Collaborations, are reviewed. The measurement of the diffractive structure function at HERA is presented, and the pomeron…
A model for deeply virtual Compton scattering, based on analytical light-cone hadron wave functions is presented and studied at energies currently accessible at Jefferson Laboratory, DESY, and beyond. It is shown that perpendicular vector…
Diffractive processes in photon-proton interactions at HERA offer the opportunity to improve the understanding of the transition between the soft, non-perturbative regime in hadronic interactions at $Q^2 = 0$ and the perturbative region at…
A measurement is presented of elastic deeply virtual Compton scattering \gamma* p \to \gamma p made using e^+ p collision data corresponding to a luminosity of 46.5 pb^{-1}, taken with the H1 detector at HERA. The cross section is measured…
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…
Future prospects of hard diffraction at HERA a reviewed. A selection of processes which can be calculated in pQCD is given, with emphasis on the separation of soft and hard diffraction. The main focus will be put on the energy dependence of…
Hard exclusive reactions are the tool to learn about generalized parton distributions, which provide a more complete parametrization of the nucleon than the ordinary parton distribution functions. Recent measurements by the HERMES…
We present a simultaneous analysis, within an impact parameter dependent saturated dipole model, of exclusive diffractive vector meson (J/psi, phi and rho) production, deeply virtual Compton scattering and the total gamma* p cross section…
Results on Deeply Virtual Compton Scattering at HERA measured by the H1 and ZEUS Collaborations are presented. The cross section, measured for the first time, is reported for Q^2 > 2 GeV^2.
Standard parton distribution functions contain neither information on the correlations between partons nor on their transverse motion, then a vital knowledge about the three dimensional structure of the nucleon is lost. Hard exclusive…
This report summarizes recent results on diffraction obtained at HERA, at the Tevatron and by the fixed target experiment E665. The measurements include vector meson production, inclusive diffraction at HERA and the pomeron structure…
The exclusive diffractive production of vector mesons and real photons in ep collisions has been studied at HERA in a wide kinematic range. The most recent experimental results are presented.
Virtual photons have proven to be very efficient probes of the hadronic structure, mostly through deep inelastic scattering and related processes. The advent of high luminosity lepton beams has allowed to enlarge the studied processes to…
The physics of diffractive vector meson production in virtual photon nucleon scattering at NMC energies is reviewed. A particular attention is paid to the physical aspects of the reaction and how they influence the observables. The reaction…