Related papers: Jet Production at HERA
Photoproduction events which have two or more jets have been studied in the $W_{\gamma p}$ range 135~GeV $< W_{\gamma p} <$ 280~GeV with the ZEUS detector at HERA. A class of events is observed with little hadronic activity between the…
The structure of the photon is studied in high energy photon-proton interactions at HERA and photon-photon interactions at LEP. The status of these measurements is reviewed.
We study photoproduction of jets and single-inclusive hadrons in a polarized ep collider mode of HERA at sqrt(s)=300 GeV, examining the sensitivity of the cross sections and their asymmetries to the proton's polarized gluon distribution and…
Inclusive dijet and trijet production in deep inelastic $ep$ scattering has been measured for $10<Q^2<100$ GeV$^2$ and low Bjorken $x$, $10^{-4}<x_{\rm Bj}<10^{-2}$. The data were taken at the HERA $ep$ collider with centre-of-mass energy…
First inclusive measurements of isolated prompt photons in photoproduction at the HERA ep collider have been made with the ZEUS detector, using an integrated luminosity of 38.4 pb$^{-1}$. Cross sections are given as a function of the…
The photoproduction of prompt photons, together with an accompanying jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb^{-1}. A study of the effective transverse momentum, k_T, of partons in the…
We present calculations of the prompt photon photoproduction at HERA collider in the k_T-factorization approach. Both direct and resolved contributions are taken into account. The conservative error analisys is performed. The unintegrated…
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…
The forward-jet cross section in deep inelastic ep scattering has been measured using the ZEUS detector at HERA with an integrated luminosity of 6.36 pb^-1. The jet cross section is presented as a function of jet transverse energy squared,…
Measurements of jet shapes and subjet multiplicities in photoproduction performed by ZEUS are presented and compared to leading-logarithm parton-shower Monte Carlo models. The predicted differences on the size of gluon- and quark-initiated…
We investigate the production of a quark-antiquark pair in diffractive photon- proton scattering, approximating soft pomeron exchange by the exchange of two nonperturbative gluons. In deep inelastic scattering at HERA, events with two jets…
Inclusive jet production is studied in neutral current deep-inelastic positron-proton scattering at large four momentum transfer squared Q^2>150 GeV^2 with the H1 detector at HERA. Single and double differential inclusive jet cross sections…
We argue that existing measurements of ep collisions at HERA --in which an energetic photon is made via a QED `Compton' subprocess-- can provide rather detailed information on the photonic parton density of the proton. This function and its…
This paper presents the first analysis of diffractive photon dissociation events in deep inelastic positron-proton scattering at HERA in which the proton in the final state is detected and its momentum measured. The events are selected by…
A measurement of inclusive jet cross-sections in deep-inelastic ep scattering at HERA is presented based on data with an integrated luminosity of 21.1 pb^-1. The measurement is performed for photon virtualities Q^2 between 5 and 100 GeV^2,…
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…
HERA has provided a wealth of high precision structure function and jet production data, allowing considerable progress to be made in understanding the structure of the proton. In this paper, several of the most recent proton structure…
A search for photoproduction events which contain a rapidity gap between the two highest transverse energy jets has been conducted at HERA using the ZEUS detector. The jets have transverse energies greater than 6~GeV, and are separated by…
We study photoproduction of jets and heavy flavors in a polarized collider mode of HERA at $\sqrt{S}= 298$ GeV. We examine the sensitivity of the cross sections and their asymmetries to the proton's polarized gluon distribution and to the…
Prompt photons, together with an accompanying jet, have been studied in the photoproduction regime of ep scattering with the ZEUS detector at HERA. Predictions based on leading-logarithm parton-shower Monte Carlo models and…