相关论文: QCD aspects of leptoquark production at HERA
I present a concise review of the possible evidence for new physics at HERA and of the recent work towards a theoretical interpretation of the signal. It is not clear yet if the excess observed at large Q^2 is a resonance or a continuum…
The cross sections for the formation of scalar resonances, leptoquarks or squarks, in electron/positron-proton collisions at HERA are presented including next-to-leading order QCD corrections. Depending mildly on the mass of the resonances,…
Perturbative QCD in the high-energy limit describes the evolution of scattering amplitudes with increasing energy towards and into the so-called saturation regime. Comparisons of the predictions with experimental data for a number of…
Hadronic antenna patterns can provide a valuable diagnostic tool for probing the origin of the apparent excess of high $x,Q^2$ events at HERA. We present quantitative predictions for the distributions of soft particles and jets in standard…
We investigate to which extent an interpretation of the recently observed excess of events in the high $Q^2$ range at HERA in terms of single leptoquark production is compatible with bounds from other experiments.
Measurements of heavy quark production, particularly from HERA, their theoretical understanding and their relevance for the LHC are reviewed. The status of beauty and charm production is discussed in the context of the different components…
Theoretical predictions for the production cross sections of leptoquarks at the CERN LHC are presented including higher-order QCD corrections. These corrections reduce the dependence on the renormalization/factorization scales…
The excess of high-Q2 events recently observed in deep-inelastic positron-proton scattering at HERA has refuelled speculations on physics beyond the standard model, in particular on low-mass leptoquark-type particles. We review the…
The excess of high-$Q^2$ events found by H1 and ZEUS at HERA in $e^+p$ deep-inelastic scattering above the Standard Model prediction motivates us to calculate the NLO QCD corrections to the HERA scalar leptoquark (or squark) production…
Strong interaction physics will be ubiquitous at the Large Hadron Collider since the colliding beams consist of confined quarks and gluons. Although the main purpose of the LHC is to study the mechanism of electroweak symmetry breaking and…
The import of HERA data on heavy quark production for LHC experiments is discussed. Knowlegde of all aspects of the beauty and charm production process, viz. the parton density functions of colliding hadrons, the hard scatter, and the…
QED radiative corrections to the cross section of diffractive electro- and photoproduction of vector mesons is calculated at HERA energies. Both semi-analytical and Monte Carlo approaches are discussed and compared.
Measurements of heavy quark production at a possible future $ep$ facility, THERA, would provide valuable information on the structure of the photon. QCD cross-section predictions are made at LO for both charm and beauty production and their…
The prospects for producing leptoquarks (LQs) in ultrahigh-energy (UHE) neutrino nucleon collisions are re-examined in the light of recent interpretations of HERA data in terms of leptoquark production. We update predictions for…
The present status of the heavy-quark production theory is critically reviewed in the first contribution. The second contribution summarises the present heavy flavour data from HERA and gives an outlook of what can be expected from HERA-II.…
The latest results of beauty quark production measurements at HERA are presented. New measurements have been obtained both in the photoproduction and the deep inelastic scattering regimes. The results were compared with the NLO QCD…
The scalar and vector leptoquark pair production cross sections for deep inelastic $ep$ scattering are calculated. Estimates are presented for the search potential at HERA.
We explore interpretations of the anomaly observed by H1 and ZEUS at HERA in deep-inelastic e^+ p scattering at very large Q^2. We discuss the possibilities of new effective interactions and the production of a narrow state of mass 200 GeV…
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…
A summary is given on the experimental bounds for the couplings and masses of scalar and vector leptoquarks associated to the first fermion generation. We investigate to which extent an interpretation of the recently reported excess of…