Related papers: Particle production and saturation at HERA
Results on diffractive scattering observed at HERA and at the TEVATRON are reviewed. This includes the extraction of diffractive parton density functions and determination of the rapidity gap survival probability at HERA and the observation…
A measurement is presented of single- and double-differential dijet cross sections in diffractive deep-inelastic $ep$ scattering at HERA using data collected by the H1 experiment corresponding to an integrated luminosity of 290 pb^{-1}. The…
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…
We comment on theoretical aspects of the measurement of azimuthal asymmetries in semi-inclusive charged particle production, made recently by the ZEUS Collaboration at HERA. By taking the ratio of the two measured asymmetries, we find good…
In the perturbative QCD with $N_c\to\infty$ equations for the amplitude of the nucleus-nucleus scattering are derived by the effective field method. The asymptotic form of the solution is discussed. It is argued that in the high-energy…
Recent results on jet cross sections and heavy-flavor production in photoproduction and neutral current deep inelastic ep scattering from the H1 and ZEUS Collaborations are presented. The jet measurements are used to perform stringent tests…
We investigate a production process $e^+p \to \st X \to \sb W^+ X$ at HERA, where we consider a decay mode $\sb \to \bar{\nu}_e d$ of the sbottom in the framework of an R-parity breaking supersymmetric standard model. Both processes of the…
Theoretical interpretations of the high-Q^2 events recently observed in deep-inelastic positron-proton scattering at HERA are reviewed. We discuss leptoquarks, squarks with R-parity violating couplings, and contact interactions. Bounds from…
We investigate the rapidity and transverse momentum distributions of the prompt photon production at the CERN LHC energies considering the current perturbative QCD approaches for this scattering process. Namely, we compare the predictions…
Two-jet cross sections in deep inelastic scattering at HERA are calculated in next-to-leading order. The QCD corrections are implemented in a new $ep\rightarrow n$ jets event generator, MEPJET, which allows to analyze arbitrary jet…
Two-jet cross sections in deep inelastic scattering at HERA are calculated in next-to-leading order. The importance of higher order corrections and recombination scheme dependencies is studied for various jetalgorithms. Some implications…
Multiparticle production at high energies is described in terms of color strings stretched between the projectile and target. As the string density increases, overlap in the transverse plane leads to cluster formation. At some critical…
We present a short summary of parton saturation concepts as seen in deep inelastic scattering.
Data on jet production in deep inelastic e^+ p scattering are presented. The results are compared with pQCD calculations. At low Q^2 no consistent description of the data over all the phase space is available yet. At high Q^2 (>150 GeV^2)…
We expect to observe parton saturation in a future electron - ion collider. In this letter we discuss this expectation in more detail considering two different models which are in good agreement with the existing experimental data on…
At very high energies or small values of Bjorken x, the density of partons, per unit transverse area, in hadronic wavefunctions becomes very large leading to a saturation of partonic distributions. When the scale corresponding to the…
Through a determination of the $S$-matrix element for the scattering of a localized colour dipole on a proton, we show that saturation effects can already be sizable at HERA. The saturation scale is found to be around 1-1.5 $GeV^2$ for the…
Inclusive jet and multijet cross sections measured in ep collisions in different kinematic regions by the H1 and ZEUS experiments are shown. The measurements are used to extract the strong coupling alpha_s as a function of the scale and at…
The multiplicity of charged hadrons in the current fragmentation region of both the c.m.s. and the Breit frame of deep inelastic scattering is calculated and compared with the HERA data. The results are in agreeement with Yang's hypothesis…
Coherence phenomena, and the non-universality of parton structure of the effective Pomeron are explained. New hard phenomena directly calculable in QCD such as diffractive electroproduction of states with $M^2\ll Q^2$ as well as new options…