Related papers: Hard Processes in Electron-Proton Scattering
We briefly discuss recent research on the spin-averaged parton densities of the proton, focusing on some aspects relevant to hard processes at the LHC. Specifically, after recalling the basic framework and the need for higher-order…
Since the start of HERA operation there has been considerable progress in the understanding of jet production in e p collisions. QCD calculations are now able to accommodate the hadronic structure of the virtual photon. The luminosities…
The measurement of the proton structure function at HERA is often seen as a hint for the observation of saturation in high-energy QCD e.g. through the observation of geometric scaling. Accordingly, the dipole picture provides a powerful…
We investigate the possibility that the process of phi photoproduction may have a significant hard perturbative QCD component. This suggestion is based on a study of the energy dependence of the forward phi photoproduction cross section…
An extract of recent results from the H1 and ZEUS Collaborations is shown. Various properties of quantum chromo dynamics are investigated by studying the details of the hadronic final state of high energy electron proton collisions at HERA.…
The latest results from the H1 and ZEUS collaborations which challenge the QCD description of high energy $ep$ collisions are presented. Data from HERA continue to provide precision measurements and are compared to the latest theoretical…
In this report diffractive high energy reactions are discussed in a functional integral approach where hadronic amplitudes are calculated from vacuum expectation values of lightlike Wegner-Wilson loops. In the first part we calculate…
The hadronic quark structure is investigated in the frame of high energy electron proton scattering. A phenomenological model based on the Born approximation is used to calculate the transition matrix element for the quark system forming…
Protons are bound states of the strong interaction governed by Quantum Chromodynamics (QCD). Its charge radius ($r_{E}^{p}$) is an important quantity as it characterizes the spatial distribution of the proton's charge, which is carried by…
We review a broad range of phenomena in diffraction in the context of hadron-hadron, hadron-nucleus collisions and deep inelastic lepton-proton/nucleus scattering focusing on the interplay between the perturbative QCD and non-perturbative…
Hard semiexclusive processes provide an opportunity to design effective currents to probe specific parton distributions and to probe in leading order parton distributions that fully inclusive reactions probe only via higher order…
In this contribution we present the main results of the investigation about double parton scattering (DPS) in quasi-real photon-proton interactions. We show the first evaluation of the DPS cross-section at leading-order for the four-jet…
Recent experimental results on the partonic structure of the photon and on the color singlet exchange in strong interaction processes are reviewed. At the LEP electron-positron and HERA lepton-proton colliders, complementary and consistent…
After a brief introduction into the phenomenology of instantons, results from instanton perturbation theory applied to deep-inelastic electron proton scattering are summarized. Based on event signatures derived from Monte Carlo studies,…
Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 < Q^2 < 100 GeV^2, and small values of Bjorken-x, 10^{-4} < x <…
We have completed the next-to-leading order perturbative QCD corrections to the virtual-photon exclusive differential cross sections for heavy quark production in deep-inelastic electron-proton scattering, i.e. $e + P \rightarrow Q +…
We review the main results we have obtained in the area of high-energy elastic hadron scattering and presented in this series of Workshops on Hadronic Interactions. After an introduction to some basic experimental and theoretical concepts,…
The exclusive diffractive production of vector mesons and real photons in ep collisions has been studied at HERA in a wide kinematic range. The most recent experimental results are presented.
We present a quantitative assessment of the impact a future Electron-Ion Collider would have in the determination of parton distribution functions in the proton and parton-to-hadron fragmentation functions through semi-inclusive…
It is shown that the hadronic dissociation of space-like $(Q^2>0)$ photons can be directly probed by performing measurements in the fragmentation region of transversely polarized and unpolarized proton beams at the electron-proton collider…