Related papers: Can one probe the structure function of the pomero…
We present a model based on a dipole picture with a hard and a soft pomeron in which large dipoles couple to the soft pomeron and small dipoles couple to the hard pomeron. The parameters in the model are fixed by proton-proton scattering…
Neutral and charged current deep inelastic scattering cross sections and structure functions are presented. The review also discusses improvements to the parton density measurements using jet cross section data and recent high $Q^{2}$…
A new generation of experiments is expected to shed light on the elusive parton structure of the bound proton. One of the most promising directions is incoherent deeply virtual Compton scattering, which can provide a tomographic view of the…
In this talk, I focus on the quark-gluon structure of hadrons probed using high-energy hadron beams. I start with a brief review on recent major achievements in measuring parton distributions of the nucleon, pion, and kaon, with hadron…
Measurements of di-jet production at HERA provide an important test of NLO QCD calculations. It is also a source of information about partonic content of the photon, complementary to the measurements in e+e- experiments. In this article we…
We discuss the perturbative QCD description of diffractive deep-inelastic scattering, and extract diffractive parton distributions from recent HERA data. The asymptotic collinear factorisation theorem has important modifications in the…
We present preliminary results for an updated extraction of the transversity parton distribution based on the analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets in collinear factorization. Data…
Recent measurements of the diffractive deep-inelastic cross section are used to extract diffractive parton densities of the proton. These are subsequently applied in models to predict the production of jets and open charm in the final…
Recent progress on the parton distribution functions of the photon, both real and virtual, is briefly reviewed and experimental possibilities at HERA are discussed.
We test the hypothesis that diffractive scattering in the perturbative and non-perturbative domain is determined by the exchange of a single pomeron with a scale dependent trajectory. Present data on diffractive vector meson production are…
We consider the dependencies of spin asymmetries in the diffractive $J/\Psi$ and $Q \bar Q$ leptoproduction at HERA energies on the structure of the pomeron-proton coupling. It is shown that it is difficult to study the spin structure of…
Development of concepts related to the photon and its high energy hadronic interaction is briefly reviewed. A photon considered as an ideal probe of hadron structure, paradoxically is also considered as an ideal target to test the…
The case of the low invariant mass exclusive central diffractive production is considered in the general theoretical framework. It is shown that diffractive patterns (differential cross-sections on variables like transfer momenta squared,…
In this talk I first briefly explain the puzzle presented by the high muon content observed in air-showers which point to the ultra high-energy $\gamma$ sources like the HER-X-1. Since it had been suggested that a possible explanation of…
Diffractive processes in photon-proton interactions at HERA offer the opportunity to improve the understanding of the transition between the soft, non-perturbative regime in hadronic interactions at $Q^2 = 0$ and the perturbative region at…
The partonic structure of hadrons plays an important role in a vast array of high-energy and nuclear physics experiments. It also underpins the theoretical understanding of hadron structure. Recent developments in lattice QCD offer new…
The observation of the quark transversity distribution requires another soft object sensitive to the quark's transverse spin. Dihadron fragmentation functions represent a convenient tool to analyze partonic spin, which can influence the…
First measurements are presented of the diffractive cross section $\sigma_{ep \rightarrow eXY}$ at centre-of-mass energies $\sqrt{s}$ of 225 and 252 GeV, together with a precise new measurement at $\sqrt{s}$ of 319 GeV, using data taken…
QED Compton scattering at HERA is discussed in terms of the information it may reveal on the proton structure at low momentum transfers Q2. Detailed Monte Carlo studies are performed which show that the analysis of inelastic QED Compton…
We determine diffractive parton distributions of the proton from DGLAP based fits to HERA data including the twist--4 contribution from longitudinal polarized virtual photons, which is known to be important in the region of large beta. The…