Related papers: Deeply virtual vector meson electroproduction at s…
Exclusive meson leptoproduction from nucleons in the deeply virtual exchanged boson limit can be described by generalized parton distributions (GPDs). Including spin dependence in the description requires 8 independent quark-parton and…
We show that the lowest-order QCD calculation in a simple model of elastic vector-meson production does reproduce correctly the ratios of cross sections for rho, phi and J/psi, both in photoproduction and in high-Q2 quasi-elastic…
The feasibility of measuring parton distribution functions of of virtual photons via the jet production at HERA is investigated.
Photoproduction of vector mesons are computed in dipole model in proton-proton ultraperipheral collisions(UPCs) at the CERN Large Hadron Collider (LHC). The dipole model framework is employed in the calculations of vector mesons production…
High transverse momentum pi0-mesons have been measured with the H1 detector at HERA in deep-inelastic ep scattering events at low Bjorken-x, down to x <~ 4.10^{-5}. The measurement is performed in a region of small angles with respect to…
We discuss how photoproduction and electroproduction processes will provide a precise tool to study nuclear structure in the small-$x$ region in the future Electron-Ion Collider. In particular, we emphasize how exclusive vector meson…
We use perturbative QCD, beyond the leading $\ln Q^2$ approximation, to show how measurements of diffractive $J/\psi$ production at HERA can provide a sensitive probe of the gluon density of the proton at small values of Bjorken $x$. We…
Elastic production of vector mesons $\gamma^{*} N\to V N$ is the pomeron-exchange dominated diffractive reaction with much potential of probing the BFKL pomeron. The BFKL pomeron can conveniently be described in terms of the dipole cross…
The process of a light neutral vector meson electroproduction is studied in the framework of QCD factorization in which the amplitude factorizes in a convolution of the nonperturbative meson distribution amplitude and the generalized parton…
Triple differential dijet cross-sections in electron proton interactions measured with the H1 detector at HERA are presented. The data are compared to Monte Carlo simulations based on the DGLAP and CCFM parton evolution schemes. Effects of…
We discuss how the dijet azimuthal correlations in DIS and real photoproduction at HERA probe the differential (unintegrated) gluon distribution in the proton. We find a strong dependence of the azimuthal correlation pattern on Bjorken-$x$,…
Assuming the proton's light-cone wave function to be dominated by small parton virtualities and small intrinsic transverse momenta, we show that the electroproduction amplitudes at large momentum transfer factorize into parton-level…
Developments in strangeness photo- and electro- production off the proton, as investigated using the CLAS system in Hall B at Jefferson Lab, are discussed in this paper. By measuring sufficient spin observables one can decompose the…
An overview of recent results from the H1 and ZEUS collaborations on vector meson production in electron-proton collisions at HERA is given. For diffractive vector meson production the energy dependence is discussed. The dependences on…
A general analysis of polarization phenomena for coherent meson electroproduction on deuterons, $e+ d\to e+ d +P^0$, where $P^0$ is a pseudoscalar $\pi ^0$ or $\eta$-meson, is presented. The spin structure of the electromagnetic current for…
We discuss exclusive $\phi$-meson electroproduction off the proton near threshold within the GPD factorization framework. We propose the `threshold approximation' in which only the leading term of the conformal partial wave expansion of the…
The proposed measurement is a dedicated study to investigate the exclusive electroproduction process: 1H(e, e'p)X, in the backward angle above the resonance region. Here, the produced particle X (pi0 or gamma) is emitted 180 degrees…
At moderately low momentum transfer (-t up to 1 GeV^2) the coupling to the vector meson production channels gives the dominant contribution to real Compton and deeply virtual Compton scattering (DVCS). Starting from a Regge Pole approach…
A compilation of H1 and ZEUS cross section measurements for elastic vector meson production is presented as a function of the scale $K^2 = (Q^2+M_V^2)/4$, where Q^2 is the exchanged photon virtuality and M_V is the mass of the vector meson.…
The parton densities of the proton are of fundamental importance not only for our description of hadronic and nuclear structure, but also for reliable predictions for new heavy particle searches at colliders. At the large partonic momentum…