Related papers: Radiative four-fermion processes at LEP2
The Monte Carlo program {\tt WWGENPV}, designed for computing distributions and generating events for four-fermion production in $e^+ e^- $ collisions, is described. The new version, 2.0, includes the full set of the electroweak (EW)…
We discuss exclusive production of lepton-antilepton, quark-antiquark, $\pi \pi$ and $\rho^0 \rho^0$ pairs in ultraperipheral, ultrarelativistic heavy-ion collisions. The cross sections for exclusive production of pairs of particles is…
Fermion compositeness, and other types of new physics that can be described by the exchange of very massive particles, can manifest themselves as the result of an effective four-fermion contact interaction. In the case of the processes…
We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo generator RacoonWW. The program RacoonWW includes the complete O(alpha) electroweak…
Lepton flavor violating interactions are absent in the standard model but are expected in various beyond standard models. In this work, the potential of the future circular electron-positron collider to probe the four fermion lepton flavor…
A remarkable number of studies have been performed at LEP in the field of two-photon physics in the last four years. These results represent a very important contribution to the understanding of strong interactions at low energies. In…
An overview of the latest results of the LEP collaborations on QCD measurements in photon-photon collisions is presented, including measurements of the total hadronic cross-section, the production of heavy quarks and dijets and the…
The cross sections for the reaction $e^+ e^- \rightarrow l \bar l q \bar q $ and for similar four fermion production processes at LEP~1, LEP~2 and the NLC are calculated. Due to the extraordinary symmetry properties of the process, very…
Theoretical calculations for the W-pair production process at LEP2 in terms of Monte Carlo event generators RacoonWW and KorlaW&YFSWW3 are reviewed. The discussion concentrates on precision predictions for the main LEP2 WW observables. The…
Four-fermion final states qqbar e+e- and qqbar mu+mu- from neutral-current interactions in e+e- collisions are studied in the OPAL detector at LEP at centre-of-mass energies from 183 GeV to 209 GeV. The data analysed correspond to a total…
Electron-positron annihilation into hadrons plus an energetic photon from initial state radiation allows the hadronic cross-section to be measured over a wide range of energies. The full next-to-leading order QED corrections for the…
We present a fully differential calculation of lepton pair production, taking into account the dominant next-to-next-to-leading order QED corrections as well as next-to-leading order electroweak and polarisation effects. We include all…
We describe the Monte Carlo event generator WOPPER for four fermion production through W-pairs including resummed leading logarithmic QED radiative corrections.
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…
At $e^+e^-$ and $ep$ colliders, the large fluxes of almost on-shell photons accompanying the lepton beams lead to the photoproduction of jets. As the centre-of-mass energy is increased, regions of smaller $x$ in the parton densities are…
Cross-section and angular distributions for hadronic and lepton-pair final states in e+e- collisions at centre-of-mass energies between 189 GeV and 209 GeV, measured with the OPAL detector at LEP, are presented and compared with the…
At present paper we performed a detailed numerical analysis of four charged leptons photoproduction in frame of standard theory of electroweak interaction. Total and differential cross sections are obtained by using of the Monte-Carlo…
The structure functions of real and virtual photons are derived from cross section measurements of the reaction e^+e^ -> e^+e^- + hadrons at LEP. The reaction is studied at \sqrt{s} ~ 91 GeV with the L3 detector. One of the final state…
The production of charged hadrons and jets is measured in collisions of quasi-real photons. The data were taken with the OPAL detector at LEP at e+e- centre-of-mass energies of 161 and 172 GeV. The measured cross-sections are compared to…
A partisan review of some of the most important $\gamma\gamma$ channels accessible at LEP 2, with special stress on the measurement of the photon structure function $F_{2}^{\gamma}$ and on associated problems with Monte Carlo modelling.