J. Lefrancois

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The inclusive production of the ω(782) vector meson in hadronic Z decays is measured and compared to model predictions. The analysis is based on 4 million hadronic Z decays recorded by the ALEPH detector between 1991 and 1995. The production rate for x p = p meson /p beam > 0.05 is measured in the ω → π + π − π 0 decay mode and found to be 0.585 ± 0.019(More)
The depression of evoked cortical potentials caused by brief periods of cerebral ischemia is attenuated by prior intracarotid injection of cytidoline (2, 4 or 8 mg/kg). Studies performed in hypercapnic cats suggest that the protection afforded by cytidoline is of metabolic rather than hemodynamic origin. The participation of the central dopaminergic(More)
Measurement of ψ(2S) meson production in pp collisions at √ s = 7 TeV Abstract The differential cross-section for the inclusive production of ψ(2S) mesons in pp collisions at √ s = 7 TeV has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb −1. The ψ(2S) mesons are reconstructed in the decay channels(More)
Using pp collision data corresponding to an integrated luminosity of 1.0 fb(-1) and collected by LHCb in 2011 at a center-of-mass energy of 7 TeV, we report the measurement of direct CP violation in B(s)(0)→K(-)π(+) decays, A(CP)(B(s)(0)→K(-)π(+)=0.27±0.04 (stat)±0.01 (syst), with significance exceeding 5 standard deviations. This is the first observation(More)
Resonant structures in B^{0}→ψ^{'}π^{-}K^{+} decays are analyzed by performing a four-dimensional fit of the decay amplitude, using pp collision data corresponding to 3  fb^{-1} collected with the LHCb detector. The data cannot be described with K^{+}π^{-} resonances alone, which is confirmed with a model-independent approach. A highly significant(More)
Measurement of charged particle multiplicities and densities in pp collisions at √ s = 7 TeV in the forward region Abstract Charged particle multiplicities are studied in proton–proton collisions in the forward region at a centre-of-mass energy of √ s = 7 TeV with data collected by the LHCb detector. The forward spectrometer allows access to a kine-matic(More)
An angular analysis of the decay J /ψ → μ + μ − is performed to measure the polarization of prompt J /ψ mesons produced in pp collisions at √ s = 7 TeV. The dataset corresponds to an integrated luminosity of 0.37 fb −1 collected with the LHCb detector. The measurement is presented as a function of transverse momentum, p T , and rapid-ity, y, of the J /ψ(More)
We present a solution made out of Components Out of Shelf (COTS) for the analog processing of the signal of the LHCb calorimeters in the framework of the foreseen upgrade of the detector. The present proposal is based on the current functional solution, yet, to meet the stringent noise requirements, a number of modifications are proposed. Preliminary(More)
A search for the rare decays B(s)(0)→μ+ μ- and B(0)→μ+ μ- is performed with data collected in 2011 and 2012 with the LHCb experiment at the Large Hadron Collider. The data samples comprise 1.1  fb(-1) of proton-proton collisions at sqrt[s]=8  TeV and 1.0  fb(-1) at sqrt[s]=7  TeV. We observe an excess of B(s)(0)→μ+ μ- candidates with respect to the(More)
The angular distributions and the partial branching fraction of the decay B0 → K*0 μ+ μ- are studied by using an integrated luminosity of 0.37  fb(-1) of data collected with the LHCb detector. The forward-backward asymmetry of the muons, A(FB), the fraction of longitudinal polarization, F(L), and the partial branching fraction dB/dq2 are determined as a(More)