Related papers: Multiparton interactions in ep scattering at HERA
We study photoproduction of jets and heavy flavors in a polarized collider mode of HERA and in polarized $ep$ collisions at $\sqrt{S}\approx 30$ GeV. We examine the sensitivity of the cross sections and their asymmetries to the proton's…
At $e^+e^-$ and $ep$ colliders, the large fluxes of almost on-shell photons accompanying the lepton beams lead to the photoproduction of jets. As the centre-of-mass energy is increased, regions of smaller $x$ in the parton densities are…
Jet and charm quark production in diffractive interactions is sensitive to the partonic structure of the diffractive exchange. This article reviews recent cross section measurements of such processes in both deep-inelastic scattering (DIS)…
Photoproduction of 2-jet events is studied with the H1 detector at HERA. Parton cross sections are extracted from the data by an unfolding method using leading order parton-jet correlations of a QCD generator. The gluon distribution in the…
The inclusive photoproduction of D\ast mesons and of D\ast-tagged dijets is investigated with the H1 detector at the ep collider HERA. The kinematic region covers small photon virtualities Q2 < 2 GeV2 and photon-proton centre-of-mass…
Many important QCD tests with jets and prompt photons have been performed with the experiments H1 and ZEUS at the HERA ep collider. This contribution focuses on results from jet and prompt photon photoproduction. In particular, the concept…
We discuss heavy quark and quarkonium production in various kinematic regions at the HERA ep collider. In contrast to fixed target experiments, collider kinematics allows the possibility of detailed measurements of particle production in…
Recent results from the ep (electron-proton) collider HERA are presented. Jet production and diffraction type reactions allow tests of predictions of Quantum Chromodynamics (QCD). Jet measurements are used to improve the combined H1-ZEUS…
The photoproduction of Drell-Yan lepton pairs at HERA is studied. We show that in the backward rapidity region the cross section is strongly sensitive to the small-$x$ behaviour of the quark distributions in the proton, and that with…
A measurement of the inclusive cross-section for the photoproduction of protons in the central fragmentation region at HERA is presented. The measured cross-section is compared with the prediction of the PYTHIA MC model. The obtained value…
The production of hard di-jet events in photoproduction at HERA is dominated by resolved photon processes in which a parton in the photon with momentum fraction x_gamma is scattered from a parton in the proton. These processes are sensitive…
We present results from NLO QCD calculations on the production of jets in ep collisions at HERA in a continuous range of photon virtuality Q^2. Special attention is given to the collinear singularities from the virtual photon and the…
A measurement is presented of dijet and 3-jet cross sections in low-|t| diffractive deep-inelastic scattering interactions of the type ep -> eXY, where the system X is separated by a large rapidity gap from a low-mass baryonic system Y.…
Deeply inelastic scattering of electrons off nuclei can determine whether parton distributions saturate at HERA energies. If so, this phenomenon will also tell us a great deal about how particles are produced, and whether they equilibrate,…
Photoproduction of jets at HERA provides information on the partonic structure of the photon. We report on the latest dijet photoproduction results, for real photons and for photons at low virtualities, measured with the ZEUS detector.
Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to…
We demonstrate that a future high-energy electron-proton collider like THERA could largely extend the current HERA program in jet photoproduction of testing QCD and determining the partonic structure of the proton and the photon. Depending…
Analyses of event shapes and forward jet production in deep inelastic scattering at the HERA collider are described. The results are compared to QCD predictions.
HERA measurements of diffractive ep scattering - the quasi-elastic scattering of the photon in the proton colour field - are summarised. Emphasis is placed on the most recent data.
Results on isolated prompt photon production are presented. The measurements were performed at HERA in deep inelastic ep scattering and photoproduction, as well as at LEP in photon photon collisions. Differential cross sections are shown…