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Measurement of the cross section for open-beauty production in photon-photon collisions at LEP
(2005)Physics Letters BJournal Article -
Measurement of the shadowing of high-energy cosmic rays by the Moon: A search for TeV-energy antiprotons
(2005)Astroparticle PhysicsJournal Article -
Search for scalar letpons and scalar quarks at LEP
(2004)Physics Letters BScalar partners of quarks and leptons, predicted in supersymmetric models, are searched for in e+e− collisions at centre-of-mass energies between 192 and 209 GeV at LEP. No evidence for any such particle is found in a data sample of 450 pb−1. Upper limits on their production cross sections are set and lower limits on their masses are derived in the framework of the Minimal Supersymmetric Standard Model.Journal Article -
Measurement of the mass and the width of the W boson at LEP
(2006)The European Physical Journal CThe mass and the total decay width of the W boson are measured with the L3 detector at the LEP e+e– collider using W-boson pairs produced in 0.7 fb–1 of data collected at centre-of-mass energies between 161 and 209 GeV. Combining semi-leptonic and fully-hadronic final states, the mass and the width of the W boson are determined to be mW=80.270±0.046±0.031GeVandΓW=2.18±0.11±0.09GeV where the first uncertainty is statistical and the ...Journal Article -
Single- and multi-photon events with missing energy in e+e- collisions at LEP
(2004)Physics Letters BSingle- and multi-photon events with missing energy are selected in 619 pb−1 of data collected by the L3 detector at LEP at centre-of-mass energies between 189 and 209 GeV. The cross sections of the process e+e−→ν ̄νγ (γ ) are found to be in agreement with the Standard Model expectations, and the number of light neutrino species is determined, including lower energy data, to be Nν=2.98±0.05±0.04. Selection results are given in the form ...Journal Article -
Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01
(2007)Physics Letters BA measurement of the cosmic ray positron fraction e+ / (e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 106 is reached by identifying converted bremsstrahlung photons emitted from positrons.Journal Article -
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Measurement of exclusive ρ0ρ0 production in two-photon collisions at high Q2 at LEP
(2003)Physics Letters BExclusive ρ0ρ0 production in two-photon collisions involving a single highly virtual photon is studied with data collected at LEP at centre-of-mass energies 89 GeV < √s < 209 GeV with a total integrated luminosity of 854.7 pb-1. The cross section of the process γγ* → ρ0ρ0 is determined as a function of the photon virtuality, Q2, and the two-photon centre-of-mass energy, Wγγ, in the kinematic region: 1.2 GeV2 < Q2 < 30 GeV2 and 1.1 GeV < ...Journal Article -
Neutral-current four-fermion production in e+e- interactions at LEP
(2005)Physics Letters BNeutral-current four-fermion production, e+e -→ff̄f′f̄′, is studied in 0.7 fb -1 of data collected with the L3 detector at LEP at centre-of-mass energies s=183-209 GeV. Four final states are considered: qq̄νν̄ , qq̄ℓ+ℓ-, ℓ+ℓ-ℓ′+ℓ′- and ℓ+ℓ-νν̄, where ℓ denotes either an electron or a muon. Their cross sections are measured and found to agree with the Standard Model predictions. In addition, the e+e-→Zγ *→ff̄f′f̄′ process is studied and ...Journal Article