7 research outputs found

    Measurement of the WZWZ Cross Section and Triple Gauge Couplings in ppˉp \bar p Collisions at s=1.96\sqrt{s} = 1.96 TeV

    Get PDF
    This Letter describes the current most precise measurement of the WZWZ production cross section as well as limits on anomalous WWZWWZ couplings at a center-of-mass energy of 1.96 TeV in proton-antiproton collisions for the Collider Detector at Fermilab (CDF). WZWZ candidates are reconstructed from decays containing three charged leptons and missing energy from a neutrino, where the charged leptons are either electrons or muons. Using data collected by the CDF II detector (7.1 fb1^{-1} of integrated luminosity), 63 candidate events are observed with the expected background contributing 8±18 \pm 1 events. The measured total cross section σ(ppˉWZ)=3.930.53+0.60(stat)0.46+0.59(syst)\sigma (p \bar p \to WZ) = 3.93_{-0.53}^{+0.60}(\text{stat})_{-0.46}^{+0.59}(\text{syst}) pb is in good agreement with the standard model prediction of 3.50±0.213.50\pm 0.21. The same sample is used to set limits on anomalous WWZWWZ couplings.Comment: Resubmission to PRD-RC after acceptance (27 July 2012

    Measurement of the Bs Lifetime in Fully and Partially Reconstructed Bs -> Ds- (phi pi-)X Decays in pbar-p Collisions at sqrt(s) = 1.96 TeV

    Get PDF
    We present a measurement of the Bs lifetime in fully and partially reconstructed Bs -> Ds(phi pi)X decays in 1.3 fb-1 of pbar-p collisions at sqrt(s) = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We measure tau(Bs) = 1.518 +/- 0.041 (stat.) +/- 0.027 (syst.) ps. The ratio of this result and the world average B0 lifetime yields tau(Bs)/tau(B0) = 0.99 +/-0.03, which is in agreement with recent theoretical predictions.Comment: submitted to Phys. Rev. Let

    Observation of the Y(4140)Y(4140) structure in the J/ψϕJ/\psi\,\phi Mass Spectrum in B±J/ψϕKB^\pm\to J/\psi\,\phi K cays

    Get PDF
    The observation of the Y(4140)Y(4140) structure in B±J/ψϕK±B^\pm\rightarrow J/\psi\,\phi K^\pm decays produced in pˉp\bar{p} p collisions at \sqrt{s}=1.96~\TeV is reported with a statistical significance greater than 5 standard deviations. A fit to the J/ψϕJ/\psi\,\phi mass spectrum is performed assuming the presence of a Breit-Wigner resonance. The fit yields a signal of 195+619^{+6}_{-5} resonance events, and resonance mass and width of 4143.4^{+2.9}_{-3.0}(\mathrm{stat})\pm0.6(\mathrm{syst})~\MeVcc and 15.3^{+10.4}_{-6.1}(\mathrm{stat})\pm2.5(\mathrm{syst})~\MeVcc respectively. The parameters of this resonance-like structure are consistent with values reported from an earlier CDF analysis.Comment: 7 pages, 2 figures, submited to Phys. Rev. Let

    Combination of CDF and D0 results on the W boson mass and width

    No full text
    The results based on 1992–95 data (Run 1) from the CDF and D0 experiments on the measurements of the W boson mass and width are presented, along with the combined results. We report a Tevatron collider average MW=80.456±0.059  GeV. We also report the Tevatron collider average of the directly measured W boson width ΓW=2.115±0.105  GeV. We describe a new joint analysis of the direct W mass and width measurements. Assuming the validity of the standard model, we combine the directly measured W boson width with the width extracted from the ratio of W and Z boson leptonic partial cross sections. This combined result for the Tevatron is ΓW=2.135±0.050  GeV. Finally, we use the measurements of the direct total W width and the leptonic branching ratio to extract the leptonic partial width Γ(W→eν)=224±13  MeV

    Causes of preventable drug-related hospital admissions: a qualitative study

    Get PDF
    Objective: To explore the causes of preventable drug-related admissions (PDRAs) to hospital. Design: Qualitative case studies using semi-structured interviews and medical record review; data analysed using a framework derived from Reason's model of organisational accidents and cascade analysis. Participants: 62 participants, including 18 patients, 8 informal carers, 17 general practitioners, 12 community pharmacists, 3 practice nurses and 4 other members of healthcare staff, involved in events leading up to the patients' hospital admissions. Setting: Nottingham, UK. Results: PDRAs are associated with problems at multiple stages in the medication use process, including prescribing, dispensing, administration, monitoring and help seeking. The main causes of these problems are communication failures ( between patients and healthcare professionals and different groups of healthcare professionals) and knowledge gaps ( about drugs and patients' medical and medication histories). The causes of PDRAs are similar irrespective of whether the hospital admission is associated with a prescribing, monitoring or patient adherence problem. Conclusions: The causes of PDRAs are multifaceted and complex. Technical solutions to PDRAs will need to take account of this complexity and are unlikely to be sufficient on their own. Interventions targeting the human causes of PDRAs are also necessary - for example, improving methods of communication

    Autoridades interpretativas: una perspectiva teórica sobre datificación y producción de sentido

    Get PDF
    Este artículo emerge en el espacio de contacto entre la literatura actual –de corte mayormente anglosajón– sobre datificación, y la perspectiva de Eliseo Verón como un aporte latinoamericano que abre oportunidades teóricas y empíricas para la discusión crítica de los procesos de datificación. Siguiendo la perspectiva de veroniana, la reflexión sobre los procesos de producción, circulación, y reconocimiento de los datos ayuda a desnaturalizar la idea de que el dato es neutral o compacto, para visibilizar, en cambio, las condiciones desde las que esos datos son provistos de sentido en tanto que constructos discursivos social y culturalmente situados. Frente a otras perspectivas anglosajonas que parecen más populares en la academia –i.e., el modelo Encoding/decoding de Hall–, este artículo propone revisitar la descripción de la articulación entre sentido y circulación por parte de Verón como una alternativa para describir los procesos de interpretación que consolidan los datos como discursos. Se trata, pues, de un punto de partida para posteriores desarrollos teóricos e investigaciones empíricas,y de una apertura de la perspectiva de Eliseo Verón para contribuir y enriquecer los debates abiertos sobre datificación y sus formas de discriminación

    Invariant Mass Distribution of Jet Pairs Produced in Association with a W Boson in pp̅ Collisions at √s=1.96  TeV

    Get PDF
    We report a study of the invariant mass distribution of jet pairs produced in association with a W boson using data collected with the CDF detector which correspond to an integrated luminosity of 4.3  fb[superscript -1]. The observed distribution has an excess in the 120–160  GeV/c[superscript 2] mass range which is not described by current theoretical predictions within the statistical and systematic uncertainties. In this Letter, we report studies of the properties of this excess.National Science Foundation (U.S.)United States. Dept. of EnergyAlfred P. Sloan Foundatio
    corecore