Related papers: Theoretical issues at LEP2 and LC
A review of the measurements of hadron, flavour-tagged and lepton-pair production cross-sections and lepton-pair forward-backward asymmetries performed by the four LEP experiments ALEPH, DELPHI, L3 and OPAL at energies between 130 and 183…
A study of W+W- events accomanied by hard photon radiation produced in e+e- collisions at LEP is presented. Events consistent with being two on-shell W bosons and an isolated photon are selected from 681 pb^-1 of data recorded at 180 GeV <…
The theoretical developments in the study of electromagnetic radiation in relativistic heavy-ion collisions are reviewed. The recent progress in the rates for photon and lepton pair production is discussed. Together with the improvements in…
Four-fermion production via electroweak neutral currents has been measured by all four LEP collaborations at center-of-mass energies near the Z resonance and for the first time also at energies well above the Z peak. Essentially all…
We present a study of single-W production ($e^+e^-\to e^-\bar{\nu}_e W^+$) as a new probe of the anomalous couplings at the LEP energy region. We introduce simple cuts to separate the single-W process from W-pair production and have…
In 1996, after another set of upgrades, LEP began running for the first time at center-of-mass energies above the W-pair production threshold. This new energy regime is rich in physics and offers new tests of the Standard Model, increased…
We analyze, in a rather general model where anomalous triple gauge couplings are present, the visible effects in R$_b$ (measured at LEP1), in W pair production (to be measured at LEP2) and in the muon anomalous magnetic moment (to be…
Results on LEP 2 e+e-->ffbar and gamma gamma (gamma) production are presented. These are compared with Standard Model predictions, and then used to set limits on various New Physics models, including Low Scale Gravity. Finally the status of…
The measurements resulting from the analysis of the LEP2 data have brought more strong evidence in support of the standard electroweak model. In particular the LEP2 data has revealed (i) the first determination of the SU(2) gauge bosons…
The LEP experiments are making real progress in understanding the structure of the photon, though the results do not yet give such clear demonstrations of QCD in action as the proton structure has done. Other new results are reported,…
In terms of an effective lagrangian, we examine the effect of new physics associated with third-generation fermions on b b-bar production at the Z resonance and study its implications for LEP2. We obtain the constraints on such operators…
We review the present situation in top quark physics, in these early days of Run II of the LHC. We take mostly a Standard Model perspective, showing recent results, and review the key concepts and results of the associated theoretical…
We present a study of single-W production ($\eetoenuW$) as a new probe of the anomalous couplings at the LEP energy region. The cross-section measurement of the single-W process is found to give complementary bounds on the anomalous…
We consider lepton-antilepton annihilation into a fermion-antifermion pair at variable c.m. energy. We propose for this process a simple parametrization of the virtual effects of the most general model of new physics of…
Dark matter pair production at high energy colliders may leave observable signatures in the energy and momentum spectra of the objects recoiling against the dark matter. We use LEP data on mono-photon events with large missing energy to…
I give a short report on the semi-analytical approach to off-shell W pair production. In particular, I show the effects of irreducible background diagrams of the CC11 class in the differential cross-section. Further, I study the influence…
Searches for new physics in the first year of running of LEP2, at energies of 161 and 172 GeV, are summarized. After a short review of WW results and their implications on new physics, searches for the Higgs boson and SUSY particles,…
Recent LEP results on electroweak precision measurements are reviewed. Line-shape and asymmetries analysis on the Z peak is described. Then, the consistency of the Standard Model predictions with experimental data and consequent limits on…
The limits on extra neutral gauge bosons, which could be reached at LEP2, are reviewed. Exclusion and discovery limits are discussed for f\bar f and WW production.
This paper gives an overview of some of the more interesting results obtained at LEP in tau physics: precision measurements in neutral and charged currents universality and structure, tau mass, topological and exclusive Branching Ratios.