Related papers: Leptoquarks: Pride and Prejudice
A review of the recent achievements in high energy neutrino physics and, partly, neutrino astrophysics is presented. It is argued that experiments with high energy neutrinos of natural origin can be used for a search of new physics effects…
We explore the possible interpretation of the large-$Q^2$ anomaly reported by the H1 and ZEUS collaborations in terms of stop squark production off a strange quark in the proton via an R-violating interaction. This "strange stop"…
The H1 and ZEUS collaborations have used the HERA I data to search for physics beyond the SM and to test electroweak physics in electron-proton collisions. The new period of data taking (HERA II) has started and first HERA II analyses…
This is an auspicious moment in experimental particle physics -there are large data samples at the Tevatron and a new energy regime being explored at the Large Hadron Collider with ever larger data samples. The coincidence of these two…
We study the sensitivity of HERA to new physics using the helicity suppressed reaction $e_R p \rightarrow \nu X $, where the final neutrino can be a standard model one or a heavy neutrino. The approach is model independent and is based on…
This article summarizes a talk presented at the SLAC Summer Institute 2000, SLAC, Stanford, USA. The HERA ep collider allows the measurement of the proton structure and tests of the Standard Model in a large region of phase space that has…
Recent results of searches for new physics at HERA using the complete data sample corresponding to about 0.5/fb per experiment are reviewed. Searches for leptoquarks, isolated leptons (electrons, muons and taus) and a generic search for new…
Some of the cleanest signals for new physics in the early runs of the LHC will involve strongly-produced particles which give rise to multiple leptons by undergoing cascade decays through weakly-interacting states to stable particles. Some…
In a global analysis of the latest parity-violating electron scattering measurements on nuclear targets, we demonstrate a significant improvement in the experimental knowledge of the weak neutral-current lepton-quark interactions at low…
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.…
In this talk I begin with some general discussion of model building in particle theory, emphasizing the need for motivation and testability. Three illustrative examples are then described. The first is the Left-Right model which provides an…
Some personal comments are given on some of the exciting interfaces between the physics of HERA and the LHC. These include the quantitative understanding of perturbative QCD, the possible emergence of saturation phenomena and the…
We present model independent constraints on the masses and couplings to fermions of $B$ and $L$ conserving leptoquarks. Such vector or scalar particles could have masses below 100 GeV and be produced at HERA; we list the generation…
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…
A search for physics beyond the Standard Model has been performed with high-Q^2 neutral current deep inelastic scattering events recorded with the ZEUS detector at HERA. Two data sets, e^+ p \to e^+ X and e^- p \to e^- X, with respective…
The HERA collaborations, H1 and ZEUS, have searched for physics beyond the Standard Model in ep collisions at centre-of-mass energies of up to 319 GeV. In this article the experimental results coming from the HERA I phase are summarised and…
A recent proposal seeks to explain the anomaly in the HERA high-Q^2 neutral current e^+p data by modifying the parton distribution functions at moderate-to-high-x and large Q^2. We investigate the consequences of this proposal for the HERA…
A study has been made of the physics interest and feasibility of experiments with nuclear beams in HERA. It is shown that such experiments widen considerably the horizon for probing QCD compared to that from free nucleon targets. In…
The energy available for gamma(*)gamma(*) physics at LEP2 is opening a new window on the study of diffractive phenomena, both non-perturbative and perturbative. We discuss some of the uncertainties and problems connected with the…
Several models of neutrino masses predict the existence of neutral heavy leptons. Here, we review current constraints on heavy neutrinos and apply a new formalism separating new physics from Standard Model. We discuss also the indirect…