Related papers: Diffraction at HERA
The H1 and Zeus collaborations have measured the inclusive diffractive DIS cross section ep -> eXp and these measurements are in good agreement within a normalisation uncertainty. Diffractive parton density functions (DPDFs) have been…
Surprisingly enough, the ratio of elastic to inelastic cross sections of proton interactions increases with energy in the interval correspond- ing to ISR - LHC (i.e. from 10 GeV to 10 TeV). That leads to special features of their spatial…
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…
The combination is presented of all inclusive deep inelastic scattering cross sections previously published by the H1 and ZEUS collaborations at HERA for neutral and charged current $ep$ scattering for zero beam polarisation. The data were…
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large…
Deep inelastic scattering (DIS) events, selected from 1993 data taken by the H1 experiment at HERA, are studied in the Breit frame of reference. The fragmentation function of the quark is compared with those of \ee data. It is shown that…
Data on the hadronic final state of deep-inelastic events at the ep collider HERA are reviewed. Fragmentation properties in the current region extracted from charged particle spectra are compared to e+e- and fixed target experiments at…
Inclusive transverse momentum spectra of charged particles in photoproduction events in the laboratory pseudorapidity range $-1.2<\eta<1.4$ have been measured up to $p_{T}=8\GeV $ using the ZEUS detector. Diffractive and non--diffractive…
Recent diffractive structure function measurements in deep inelastic scattering (DIS) by the H1 and ZEUS experiments at HERA are reviewed. In neutral current (NC) DIS, precise measurements have been made of diffraction, $ep \to eXY$, the…
The operation of HERA with polarized proton and electron beams will allow to study a wide variety of observables in polarized electron-proton collisions at $\sqrt s=300$ GeV. The physics prospects of this project have been elaborated in…
The production of dijets with a tagged forward proton is measured at HERA. The data were recorded with the H1 detector at DESY in the years 2006-2007. Events with a leading proton are detected using the very forward proton spectrometer of…
The study of photoproduction reactions has gained a unique opportunity with the HERA data. The high center of mass energy allows to carry out quantitative tests of QCD, to explore the substructure of both the photon and the proton and to…
We present a new mechanism for the creation of large rapidity gaps in DIS events at HERA. Soft colour interactions between perturbatively produced partons and colour-charges in the proton remnant, modifies the colour structure for…
A large collection of results for the diffractive dissociation of virtual photons, $\gamma^{\star}p \to Xp$, have been obtained with the H1 and ZEUS detectors at HERA. Different experimental techniques have been used, by requiring a large…
The cross section of the diffractive process e^+p -> e^+Xp is measured at a centre-of-mass energy of 318 GeV, where the system X contains at least two jets and the leading final state proton p is detected in the H1 Very Forward Proton…
A new method is employed to measure the neutral current cross section up to Bjorken-x values of one with the ZEUS detector at HERA using an integrated luminosity of 65.1 pb-1 for e+p collisions and 16.7 pb-1 for e-p collisions at…
At HERA, the large flux of almost real photons accompanying the electron beam leads to the copious photoproduction of jets. Regions of small momentum fractions $x$ of the incoming particles are explored, where the density of partons is…
Signals of physics beyond the Standard Model at HERA have been searched for by the H1 and ZEUS collaborations. Results are reported about searches of contact interaction effects, leptoquarks, R-parity violating squarks, excited fermions and…
The early observation at HERA of an excess of events compared to the expectation from the Standard Model in very short distance $e^+p$ deep-inelastic scattering processes has renewed the interest in the search for new physics which could…
Models based on soft colour exchanges to rearrange colour strings in the final state provide a general framework for both diffractive and non-diffractive events in ep and hadron-hadron collisions. We study two such models and find that they…