Related papers: Unintegrated gluon distribution from forward polar…
We investigate the longitudinal and transverse polarized cross-sections of the leptoproduction of the rho meson in the high energy limit. Our model is based on the computation of the impact factor gamma*(lambda_gamma) -> rho(lambda_rho)…
We systematically study exclusive diffractive (photo) production of vector mesons ($J/\psi$, $\psi(2s)$, $\phi$ and $\rho$) off protons in high-energy collisions and investigate whether the production is a sensitive probe of gluon…
We constrain proton structure fluctuations at small-$x$ by comparing with the HERA diffractive vector meson production data, and find that large geometric fluctuations in the proton wave function are needed. Hydrodynamical simulations of…
We evaluate the unintegrated gluon distribution of the proton starting from a parametrization of the color dipole cross section including DGLAP evolution and saturation effects. To this end, we perform the Fourier-Bessel transform of…
The exclusive electroproduction of J/psi mesons, ep->epJ/psi, has been studied with the ZEUS detector at HERA for virtualities of the exchanged photon in the ranges 0.15<Q^2<0.8 GeV^2 and 2<Q^2<100 GeV^2 using integrated luminosities of 69…
The recent high precision SMC data on polarized $\mu p$ scatterings have again confirmed that very little of the proton spin is carried by quarks. To unravel the mystery of the proton spin structure, it is quite important to know the…
We perform a global leading-order QCD fit to recent polarized structure function data in order to extract a consistent set of spin-dependent parton distributions. Assuming that there is no significant intrinsic polarization of the quark…
Inclusive cross sections for Higgs boson production in proton-proton collisions are calculated in the formalism of unintegrated gluon distributions (UGDF). Different UGDF from the literature are used. Although they were constructed in order…
Inelastic photoproduction of $J/\psi$ particles at high energies is one of the processes to determine the gluon distribution in the nucleon. The QCD radiative corrections to the color-singlet model of this reaction have recently been…
Gluons inside unpolarized hadrons can be linearly polarized provided they have a nonzero transverse momentum. The simplest and theoretically safest way to probe this distribution of linearly polarized gluons is through cos(2 phi)…
At high energies a quark-gluon plasma is expected to be formed in heavy ion collisions at RHIC and LHC. The theoretical description of these processes is directly associated to a complete knowledge of the details of medium effects in the…
To investigate the possible geometric structure of the proton, an improved stringy proton model is constructed beyond the smallest distance approximation, where the constituent quarks are connected by gluon tubes which merge at the Fermat…
HERA has provided a wealth of high precision structure function and jet production data, allowing considerable progress to be made in understanding the structure of the proton. In this paper, several of the most recent proton structure…
The production rates of lepton-photon and dimuon pairs at the HERA collider and the HERMES experiment are evaluated in the leading order equivalent photon approximation. It is shown that the production rates are sufficient to facilitate the…
We present a model for the polarized cross-sections of the hard diffractive leptoproduction of rho meson in the high energy limit. Our model is based on the light-cone collinear factorization of the virtual photon to rho meson impact factor…
Cross sections for elastic production of J/Psi mesons in photoproduction and electroproduction are measured in electron proton collisions at HERA using an integrated luminosity of 55 pb^{-1}. Results are presented for photon virtualities…
The results of experiments at hadron colliders probing the structure of the pomeron through hard diffraction are reviewed. Some results on deep inelastic diffractive scattering obtained at HERA are also discussed and placed in perspective.…
Dipole models based on various saturation scenarios provide reasonable fits to small-x DIS inclusive, diffractive and exclusive data from HERA. Proton un-integrated gluon distributions extracted from such fits are employed in a…
We review here two approaches to describe hard leptoproduction of transversally polarized rho-meson, based on recent calculation of the gamma*T -> rhoT impact factor up to twist 3 accuracy in the collinear factorization frame, including 2-…
I study the production of prompt photons in polarized hadronic collisions, considering different isolation prescriptions. In particular, I focus on the problem of the measurability of the polarized gluon density in the proton through…