Related papers: QCD and Diffraction at HERA
Deep-inelastic positron-proton scattering events at low photon virtuality Q^2 with a forward jet, produced at small angles with respect to the proton beam, are measured with the H1 detector at HERA. A subsample of events with an additional…
It is demonstrated that the global properties of the rapidity gap events at HERA can be understood based on electron-gluon scattering and a non-perturbative mechanism of colour neutralization. Using the measured inclusive structure function…
We describe diffractive deeply inelastic scattering in terms of diffractive parton distributions. We investigate these distributions in a hamiltonian formulation that emphasizes the spacetime picture of diffraction scattering. For hadronic…
Recent results from jet production in deep inelastic ep scattering to investigate parton dynamics at low x are reviewed. The results on jet production in deep inelastic scattering and photoproduction used to test perturbative QCD are…
We analyse the newest diffractive deep inelastic scattering data from HERA using the dipole model approach. We find a reasonable good agreement between the predictions and the data although the region of small values of a kinematic variable…
A measurement is presented of inelastic photo- and electroproduction of J/psi mesons in ep scattering at HERA. The data were recorded with the H1 detector in the period from 2004 to 2007. Single and double differential cross sections are…
The diffractive dissociation of virtual photons, gamma*p -> Xp, has been studied in ep interactions at HERA with the H1 and ZEUS detectors. The data are presented in terms of the diffractive structure function F2D and of the diffractive…
Measurements are presented of differential dijet cross sections in diffractive photoproduction (Q^2<0.01 GeV^2) and deep-inelastic scattering processes (DIS, 4<Q^2<80 GeV^2). The event topology is given by ep-> e X Y, in which the system X,…
This lecture contains a brief introduction to HERA and deep inelastic scattering (DIS), before going on to highlight some of the measurements of the hadronic final state in DIS performed by the H1 and ZEUS collaborations.
We suggest a simple physical picture for the diffractive parton distributions that appear in diffractive deeply inelastic scattering. In this picture, partons impinging on the proton can have any transverse separation, but only when the…
The production of dijets is measured in diffractive deep-inelastic scattering at HERA. The data were recorded with the H1 detector at DESY in the years 2003-2007. Diffractive events are selected by requiring a gap in the rapidity…
The process of charm quark fragmentation is studied using $D^{*\pm}$ meson production in deep-inelastic scattering as measured by the H1 detector at HERA. Two different regions of phase space are investigated defined by the presence or…
Jet production in electron-proton collisions at HERA provides a unique testing ground for Quantum Chromodynamics (QCD). Apart from the determination of the strong coupling constant $\alpha_s$, ep jet data may especially be used to gain…
We describe new QCD fits to diffractive proton structure functions measured at HERA, and we use these parton densities to predict the shape of the dijet mass fraction at the Tevatron and look for the existence of exclusive events in the…
We compute various kinematical distributions for one-jet and two-jet inclusive photoproduction at HERA. Our results are accurate to next-to-leading order in QCD. We use the subtraction method for the cancellation of infrared singularities.…
In the present talk diffraction in deep inelastic scattering is discussed in the framework of the semiclassical approach. The main emphasis is on the possibility of a consistent semiclassical description of both hard and soft colour singlet…
The HERA experiments H1 and ZEUS have recently presented a number of interesting results from studies of the hadronic final state produced in $ep$ collisions. These studies have focussed on deep inelastic scattering events and on the…
Different theoretical methods used for the description of diffractive processes in small-x deep inelastic scattering are reviewed. The semiclassical approach, where a partonic fluctuation of the incoming virtual photon scatters off a…
Following recent predictions that the geometric scaling properties of deep inelastic scattering data in inclusive gamma*-p collisions are expected also in exclusive diffractive processes, we investigate the diffractive production of vector…
We extend a quantum kinetic approach to the description of hadronic showers in space, time and momentum space to deep-inelastic $ep$ collisions, with particular reference to experiments at HERA. We follow the history of hard scattering…