Related papers: Leading twist asymmetries in deeply virtual Compto…
We study the doubly virtual Compton scattering off a spinless target $\gamma^*P\to\gamma^*P'$ within the Anti-de Sitter(AdS)/QCD formalism. We find that the general structure allowed by the Lorentz invariance and gauge invariance of the…
The main properties of the leading-twist transverse momentum dependent parton distributions in a light-cone constituent quark model of the nucleon are reviewed, with focus on the role of the spin-spin and spin-orbit correlations of quarks.…
Transverse momentum dependent parton distribution functions are a key ingredient in the description of spin and azimuthal asymmetries in deep-inelastic scattering processes. Recent results from non-perturbative calculations in effective…
We analytically calculate weighted azimuthal asymmetries in semi-inclusive lepton-nucleon deep-inelastic scattering and Drell-Yan processes, using transverse-momentum-dependent partonic densities obtained in a diquark spectator model. We…
We discuss the target and beam normal spin asymmetries in elastic electron-nucleon scattering which depend on the imaginary part of two-photon exchange processes between electron and nucleon. In particular, we estimate these transverse spin…
Predictions for deep Virtual Compton Scattering are obtained in a two-component dipole model of diffraction. The model automatically includes hard and soft components and implicitly allows for ``hadronic'' contributions via large dipoles.…
Double deeply virtual Compton scattering (DDVCS) is the process where an electron scatters off a nucleon and produces a lepton pair. The main advantage of this process in contrast with deeply virtual and timelike Compton scatterings (DVCS…
A systematic derivation is presented of the twist-2 anomalous dimensions of the general quark and gluon light-ray operators in the generalized Bjorken region in leading order both for unpolarized and polarized scattering. Various…
We consider the single-spin azimuthal asymmetries recently measured at the HERMES experiment for charged pions produced in semi-inclusive deep inelastic scattering of leptons off longitudinally polarized protons. Guided by the experimental…
The single-spin asymmetry of unpolarized leptons scattering deep-inelastically off transversely polarized nucleons is studied in a partonic picture within a collinear twist-3 framework. Since this observable is generated by multi-photon…
The Compton amplitude is calculated in terms of expectation values of light-ray quark operators. As a technical tool we apply the nonlocal light-cone expansion. Thereby we express the expectation value of the vector light-ray operator with…
We further analyze the holographic dipole-dipole scattering amplitude developed in arXiv:1202.0831, 1205.3223. Gribov diffusion at strong coupling yields the scattering amplitude in a confining background. We compare the holographic result…
We report on a calculation to show that the Fourier transform of the Deeply Virtual Compton Scattering (DVCS) amplitude with respect to the skewness variable \zeta at fixed invariant momentum transfer squared t gives results that are…
Virtual Compton scattering off the nucleon has been studied in the one-loop approximation of the linear sigma model. The three generalized polarizabilities of the nucleon have been calculated and compared with the existing theoretical…
We give predictions for the leading order amplitudes for deeply virtual Compton scattering and hard meson electroproduction reactions at large Q^2 in the valence region in terms of skewed quark distributions. We give first estimates for the…
We present a parameterization of the non-collinear (virtual) Compton scattering tensor in terms of form factors, in which the Lorentz tensor associated with each form factor possesses manifest electromagnetic gauge invariance. The main…
We study the nonforward Compton scattering in particular the deeply virtual Compton scattering from AdS/CFT. We first calculate the contributions from the s-channel and u-channel supergravity diagrams as well as the four point interaction…
A factorized Regge-pole model for deeply virtual Compton scattering is suggested. The use of an effective logarithmic Regge-Pomeron trajectory provides for the description of both ``soft'' (small $|t|$) and ``hard'' (large $|t|$) dynamics.…
A measurement of elastic deeply virtual Compton scattering gamma* p -> gamma p using e^+ p and e^- p collision data recorded with the H1 detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306…
The proton spin budget is discussed. Results are presented from inclusive and semi-inclusive deep inelastic scattering and from deeply virtual Compton scattering. They permit interpretations towards the determination of various…