Related papers: Diffractive vector meson leptoproduction and spin …
Advantages of the amplitude method for the vector-meson-production description in respect of the spin-density-matrix-element (SDME) method are discussed. It is shown that for any nonzero amplitudes the angular distribution of final…
We present a simple physical description of the off-diagonal gluon distribution g (x,x^\prime,Q^2) and splitting function P_{gg}(x,x^\prime) which enter the amplitude for diffractive vector meson production. We study the off-diagonal…
Hard exclusive production in deep inelastic lepton scattering provides access to the unknown Generalized Parton Distributions (GPDs) of the nucleon. At HERMES, different observables for hard exclusive pi^+ production have been measured with…
We evaluate the cross sections for the production of vector mesons in exclusive ultraperipheral proton-ion collisions at LHC. We find that the rates are high enough to study the energy and momentum transfer dependence of vector mesons -…
We discuss recent preliminary results on the diffractive photoproduction of {\rhoz}, $\phi$, and {\jpsi} mesons at high momentum transfer reported by the ZEUS collaboration at HERA. A special-purpose calorimeter served to tag the quasi-real…
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.
In semi-inclusive deep inelastic scattering of polarized leptons on a transversely polarized target eight target transverse spin-dependent azimuthal modulations are allowed. In the QCD parton model half of these asymmetries can be…
We demonstrate that perturbative QCD allows one to calculate the absolute cross section of diffractive exclusive production of photons at large $Q^2$ at HERA, while the aligned jet model allows one to estimate the cross section for…
In this paper we consider the process of diffraction dissociation in deep inelastic scattering producing a small mass. This process is analyzed by the calculation of $\bar q\, q$ and $\bar q\, q\, G$ production. We show that the small…
We compute cross sections for incoherent and coherent diffractive J/$\Psi$ and $\Psi(2S)$ production in ultraperipheral heavy ion collisions. The dipole models used in these calculations are obtained by fitting the HERA deep inelastic…
The diffractive scattering of photon off proton $\gamma^{(*)} p \to \gamma Y$ (where $Y$ denotes the proton dissociative system or the elastically scattered proton) is measured in two different kinematic regimes at high energy with the H1…
A review is presented of diffractive vector meson production at HERA, with stress on the investigation of ``hard'' features and comparisons with theoretical predictions based on perturbative QCD approaches.
The recent data on the polarization of vector meson at LEP show that the vector mesons favor the helicity zero state. We calculate the helicity density matrix of vector meson which contains a polarized fragmenting quark by adding the spin…
We study the production of spin-one mesons in high-energy heavy-ion collisions with peripheral kinematics in the framework of QED. The cross sections of the production of a single vector meson and of two different ones are presented. The…
We analyze light meson electroproduction within the handbag model. We study cross sections and spin asymmetries for various mesons. The essential role of the transversity $\tilde H_T$ and $\tilde E_T$ GPDs in electroproduction of…
We provide an analysis of vector meson photoproduction in the channel of the vector meson decaying into a pseudoscalar meson plus a photon, i.e. $V\to P\gamma$. It is shown that non-trivial kinematic correlations arise from the measurement…
In this work we analyse the theoretical uncertainties on the predictions for the photoproduction of light vector mesons in coherent pp, pA and AA collisions at the LHC energies using the color dipole approach. In particular, we present our…
We consider the hard leptoproduction of a photon off nuclei up to spin-1. As a new result we present here the general azimuthal angular dependence of the differential cross section for a spin-1 target. Its twist-two Fourier coefficients of…
Measurements of deeply virtual Compton scattering (DVCS) made at HERMES using 27.6 GeV $e^\pm$ beams and various internal polarized or unpolarized gaseous targets are discussed. Results are reported on the transverse target-spin asymmetry…
We study the transverse-momentum distribution of hadrons produced in semi-inclusive deep-inelastic scattering. We consider cross sections for various combinations of the polarizations of the initial lepton and nucleon or the produced…