Related papers: Has HERA reached a new QCD regime?
From the new measurement of F_L at HERA we derive fixed-Q^2 averages <F_L/F_2>. We compare these with bounds which are rigorous in the framework of the standard dipole picture. The bounds are sharpened by including information on the charm…
We study how factorization breaking changes when going from diffractive deep inelastic scattering to diffractive photoproduction of dijets. These processes offer a sensitive probe of the interplay of soft and hard mechanisms in QCD. We…
We report on an extensive global QCD analysis of new DIS and hadronic inclusive jet production data emphasizing the impact of these recent data on the determination of the gluon distribution, and on the interpretation of the high $E_t$ jets…
We study a twist decomposition of diffractive structure functions in the diffractive deep inelastic scattering (DDIS) at HERA. At low Q2 and at large energy the data exhibit a strong excess, up to about 100%, above the twist 2 NLO DGLAP…
We summarise the latest experimental QCD studies based on data from LEP. Measurements of the quark and gluon jet fragmentation functions are discussed, including a new algorithm to infer the properties of unbiased gluon jets. We describe a…
In this contribution we apply the QCD dipole picture combined with $k_T$-factorization to get predictions for deep-inelastic scattering on an onium. Assuming renormalization-group factorization, we get predictions for the $F_2, F_G$ and $R=…
Recent measurements of QCD interactions involving large momentum transfers are reviewed. The status of measurements of the strong coupling constant is summarised. Recent developments in the measurement and interpretation of deep inelastic…
Recent results from the H1 experiment [1] have confirmed the existence of a substantial baryon asymmetry of the proton sea at small $x$ with magnitude predicted in hep-ph/9607486. This is a strong support for the idea [3] that baryon number…
We extend a previous GTMD model to improve the description of the HERA data on diffractive dijet production, and include exclusive coherent diffractive $J/\psi$ production data. We find that within our gluon GTMD model context and…
We present a global analysis of available data on inclusive structure functions measured in electron-proton scattering at small values of Bjorken-x, including the latest data from the combined HERA analysis on reduced cross sections. Our…
Data from the HERA collider experiments, H1 and ZEUS, have been fundamental to the rapid recent development of our understanding of the partonic composition of the proton and of QCD. This report focuses on inclusive measurements of neutral…
H1 has measured the diffractive DIS cross section $ep \rightarrow eXY$ using data from both of the HERA data-taking periods. Using new measurements of the diffractive cross section at different centre-of-mass energies, the diffractive…
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…
The transverse momentum dependent gluon density obtained with CCFM evolution is determined from a fit to the latest combined HERA structure function measurements.
New results on diffractive deep-inelastic $e p$ scattering at HERA are presented using data taken in 1994 with the H1 detector. The cross section for diffractive deep-inelastic scattering is measured in terms of a diffractive structure…
Several important and unique measurements, within the standard model and of possible physics beyond it, could be made with {\em polarized HERA} in which both the proton and the electron beams are polarized. With a $\sim$820 GeV proton beam…
A brief survey is given of recent HERA results in jet production and prompt photon production, together with the evaluation of the QCD coupling constant alpha_s.
Recent results from the ep (electron-proton) collider HERA are presented. Jet production and diffraction type reactions allow tests of predictions of Quantum Chromodynamics (QCD). Jet measurements are used to improve the combined H1-ZEUS…
We summarize recent developments in the understanding of nucleon structure. New data on F2, R and F2c, over a wide range of Q2 and x, are described. Conventional leading twist NLO perturbative QCD gives an excellent account of all the new…
The QCD analysis of deep inelastic diffractive scattering is performed assuming the dominance of the "soft" pomeron exchange and simple, physically motivated parametrization of parton distributions in a pomeron. Results of the analysis are…