Related papers: Factorisation breaking in diffractive dijet photop…
The results of measurement of beauty quark production at HERA performed by the H1 and ZEUS collaborations are presented. Total cross sections and the differential cross sections have been measured in both the photoproduction and the deep…
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…
Differential dijet cross sections in diffractive deep-inelastic scattering are measured with the H1 detector at HERA using an integrated luminosity of 51.5 pb-1. The selected events are of the type ep --> eXY, where the system X contains at…
Analyses of jet production at HERA have become precise enough to perform QCD studies which are both competitive and complementary to those at e+e- and p-pbar colliders. This report summarises some of the latest results on jet physics from…
We report the latest results of the ZEUS collaboration on the photoproduction of D* mesons in a low W range. Differential cross sections as function of pt(D*) and eta(D*) are measured and compared with several recent NLO pQCD calculations.…
Recent NLO calculations for the photoproduction of one and two jets at HERA are compared to data from H1 and ZEUS. We discuss the physics potential of these measurements for constraining the photon structure, especially the quark density at…
Dijet production by almost real photons has been studied at HERA with the ZEUS detector. Jets have been identified using the cone algorithm. A cut on xg, the fraction of the photon energy participating in the production of the two jets of…
We have calculated inclusive two-jet cross sections in next-to-leading order QCD for direct photoproduction in low $Q^2$ $ep$ collisions at HERA. Infrared and collinear singularities in real and virtual contributions are cancelled with the…
Dijet cross sections as functions of several jet observables are measured in photoproduction using the H1 detector at HERA. The data sample comprises e^+p data with an integrated luminosity of 34.9 pb^(-1). Jets are selected using the…
Results on hard diffraction from HERA and proton-antiproton Colliders are reviewed with emphasis on the factorization properties of the diffractive structure function of the proton and on the structure of the pomeron.
Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb-1. The measurements were made in the kinematic range Q^2 < 1 GeV^2, 0.20 < y < 0.85 and x_pom <…
We study diffractive hard dijet production, with one or two rapidity gaps, at high energies. We emphasize that both hard and Regge factorization are broken in these processes. We show that a multi-Pomeron-exchange model for screening…
The cross section for photoproduction of a prompt photon in association with a jet is studied in Next-to-Leading Order at the DESY $ep$ collider HERA. The effect of various cuts imposed on the cross section by the ZEUS collaboration…
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…
At the electron-proton collider HERA the inclusive $D^{*\pm}$ meson photoproduction cross section has been measured with the H1 detector in two different, but partly overlapping, kinematical regions. For the first, where $<W_{\gamma p}>…
A new H1 measurement of diffractive dijet and 3-jet production cross sections in diffractive deep inelastic scattering events of the type ep->eXY is presented. The data constrain well the diffractive gluon distribution. At low x-pom, a…
Interactions of the type ep -> eXY are studied, where the component X of the hadronic final state contains two jets and is well separated in rapidity from a leading baryonic system Y. Analyses are performed of both resolved and direct…
Cross sections for the diffractive photoproduction of the Upsilon-family at HERA energies, within the framework of the analysis by Frankfurt, Koepf and Strikman, are presented. They compare well with the recent preliminary data from ZEUS…
A review is presented of jet substructure measurements from the H1 and ZEUS Collaborations at HERA. The results presented include tests of perturbative QCD, comparison of the properties of quark and gluon jets, the comparison of the pattern…
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…