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Related papers: LEP 2 e+e-->ffbar, gamma gamma (gamma): results an…

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Production of events with hadronic and leptonic final states has been measured in e^+e^- collisions at centre-of-mass energies of 130-172 GeV, using the OPAL detector at LEP. Cross-sections and leptonic forward-backward asymmetries are…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

The $e^{+}\,e^{-}\,\rightarrow\,l^{+}\, \l^{-}\,\gamma\,\gamma$ anomalous events, detected by $L3$ de\-tec\-tor at $e^+ e^-$ $CERN-LEP$ collider have been analysed. It has been shown that the interpretation of such events as a manifestation…

High Energy Physics - Phenomenology · Physics 2009-09-25 V. A. Litvin , S. R. Slabospitsky

Non-commutative QED would lead to deviations from the Standard Model depending on a new energy scale Lambda_NC and a unique direction in space defined by two angles eta and xi. Here in this analysis eta is defined as the angle between the…

High Energy Physics - Experiment · Physics 2012-08-27 The OPAL collaboration

The process e^+e^- -> gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 25.38 pb^{-1} taken at centre-of-mass energies of 130-172 GeV. The…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

The results on e+e- --> W+W- --> 4f(+gamma) obtained by different groups are compared with each other. Differences in the results for the total cross section of up to about 0.6% are traced back to different ways of implementing the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Yoshimasa Kurihara , Masaaki Kuroda , Dieter Schildknecht

In this note we assess the validity and uncertainties in the predictions of the eikonalised mini-jet model for $\sigma^{inel}_{\gamma \gamma}$. We are able to find a choice of parameters where the predictions are compatible with the current…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Corsetti , R. M. Godbole , G. Pancheri

W+W-gamma production at LEP2 is studied using data collected with the DELPHI detector at centre-of-mass energies between 189 GeV and 209 GeV, corresponding to an integrated luminosity of about 600 pb^-1. Cross-sections are measured for the…

High Energy Physics - Experiment · Physics 2008-11-26 The DELPHI Collaboration , J. Abdallah

The double-radiative process e+e- -> Z gamma gamma -> q q~ gamma gamma, where the two hard photons escape detection at low polar angles into opposite directions, is studied in 0.62/fb of data collected with the L3 detector at LEP at…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

Recent results on total cross-section measurements in gamma-gamma and gamma*-gamma* collisions at LEP are reported. Phenomenological fits to the data are presented.

High Energy Physics - Phenomenology · Physics 2009-11-07 A. De Roeck

A study of the radiative neutrino counting reaction $e^+ e^- \to \nu {\bar \nu} \gamma$ at LEP1 and LEP2 energies is presented. An approximate expression for the spectrum of the observed photon is derived within the framework of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. Montagna , O. Nicrosini , F. Piccinini , L. Trentadue

We study the reaction e+e- --> e+e-pi0 and measure the gamma gamma* --> pi0 transition form factor in the momentum transfer range from 4 to 40 GeV^2. The analysis is based on 442 fb^-1 of integrated luminosity collected at PEP-II with the…

High Energy Physics - Experiment · Physics 2010-04-12 The BABAR Collaboration , B. Aubert

The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL Collaboration , K. Ackerstaff et al

A summary of results obtained from e^+e^- annihilations at LEP is given. The precision measurements around the Z resonance, the results from charged gauge boson production and searches for new particles are reviewed. Particular emphasis is…

High Energy Physics - Experiment · Physics 2009-09-29 Wolfgang Lohmann

The status of the standard model is briefly reviewed in the light of the most recent set of experimental data, with particular emphasis to the limits on the Higgs boson mass. The search for a light Higgs boson at LEP~2 is also briefly…

High Energy Physics - Phenomenology · Physics 2007-05-23 Giampiero Passarino

A search for the pseudoscalar meson eta_b is performed in two-photon interactions at LEP~2 with an integrated luminosity of 699 pb^-1 collected at e+e- centre-of-mass energies from 181 GeV to 209 GeV. One candidate event is found in the…

High Energy Physics - Experiment · Physics 2012-08-27 ALEPH Collaboration

A calculation of the hard bremsstrahlung process e+ e- -> mu+ mu- gamma gamma is presented and compared with recent results from the L3 Collaboration.

High Energy Physics - Phenomenology · Physics 2009-10-22 K. Kołodziej , F. Jegerlehner , G. J. van Oldenborgh

Single- and multi-photon events with missing energy are selected in 619/pb of data collected by the L3 detector at LEP at centre-of-mass energies between 189GeV and 209GeV. The cross sections of the process e^+e^- -> nu nu gamma (gamma) are…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

The hypothetic R--resonance production (anomalous "$l\bar l\gamma\gamma$" events at LEP) with 60 GeV mass at FNAL hadron collider has been considered. The cross-section of this R-resonance production with the consequent decay $R \to…

High Energy Physics - Phenomenology · Physics 2009-09-25 V. A. Litvin , S. R. Slabospitsky , A. V. Shvorob

The cross section of the process e^+ e^- -> Z \gamma\gamma -> qq \gamma \gamma is measured with 215 pb^-1 of data collected with the L3 detector during the final LEP run at centre-of-mass energies around 205 GeV and 207 GeV. No deviation…

High Energy Physics - Experiment · Physics 2012-08-27 L3 collaboration

Recent BABAR and Belle results on rare B decays involving photons or lepton pairs are reviewed. New preliminary limits from both experiments for B-->rho gamma and B-->omega gamma, and from BABAR for B --> K nu nu and B --> tau nu are…

High Energy Physics - Experiment · Physics 2007-05-23 A. M. Eisner