It is reported on an analysis of electroproduction of light vector mesons at small Bjorken-x (xBj) within the handbag approach. The partonic subprocesses, meson electroproduction off quarks or gluons, are calculated within the modified perturbative approach (m.p.a.) in which quark transverse momenta are retained. The soft hadronic matrix elements, generalized parton distributions (GPDs), are co...

We investigate corrections to the handbag approach for wide-angle Compton scattering off protons at moderately large momentum transfer: the photon-parton subprocess is calculated to next-to-leading order in αs and contributions from the generalized parton distribution E are taken into account. Photon and proton helicity flip amplitudes are non-zero due to these corrections which leads to a weal...

A simple way to extract the Generalized Parton Distribution H(ξ, ξ, t) at small t from the single beam-spin asymmetry in Deeply Virtual Compton Scattering is proposed. Projections are given for future measurements at the HERMES experiment upgraded with a recoil detector.

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 the interference and squared deeply virtual Compton scattering amplitude are evaluated in leading order approximation of perturbation theory in terms of gene...

The determination of quark angular momentum requires the knowledge of the generalized parton distribution E in the forward limit. We assume a connection between this function and the Sivers transverse-momentum distribution, based on model calculations and theoretical considerations. Using this assumption, we show that it is possible to fit nucleon magnetic moments and semi-inclusive single-spin...