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We discuss various aspects of vector meson production, first analysing the interplay between perturbative and nonperturbative aspects of the QCD calculation. Using a general method adapted to incorporate both perturbative and nonpertubative aspects, we show that nonperturbative effects are important for all experimentally available values of the photon virtuality Q2. We compare the huge amount of experimental information now available with our theoretical results obtained using a specific nonperturbative model without free parameters, showing that quite simple features are able to explain the data.
It is reported on a global analysis of hard vector-meson electroproduction which is based on the handbag factorization. The generalized parton distributions are constructed from their forward limits with the help of double distributions and the parto
We calculate diffractive photo- and leptoproduction of $rho$-, $rho$- and $rho$-mesons. The incoming photon dissociates into a $qbar{q}$-dipole which scatters on the nucleon and transforms into a vector meson state. The scattering amplitude is calcul
In the framework of non-perturbative QCD we calculate high-energy diffractive production of vector mesons $rh, rh$ and $rh$ by real and virtual photons on a nucleon. The initial photon dissociates into a $qbar{q}$-dipole and transforms into a vector
General expressions for the unpolarized differential cross section and for various polarization observables in the coherent pseudoscalar meson photo- and electroproduction on the deuteron target have been obtained in one-photon-exchange approximation
An exact expression is derived for the meson production current off the nucleon for real and virtual photons which cleanly separates, in a model-independent manner, a tree-level expression that manifestly preserves local gauge invariance in terms of