181 research outputs found

    Compressed representation of a partially defined integer function over multiple arguments

    Get PDF
    In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one

    Averages of b-hadron, c-hadron, and tau-lepton properties as of 2018 Heavy Flavor Averaging Group (HFLAV)

    Get PDF
    This paper reports world averages of measurements of b-hadron, c-hadron, and τ -lepton properties obtained by the Heavy Flavour Averaging Group using results available through September 2018. In rare cases, significant results obtained several months later are also used. For the averaging, common input parameters used in the various analyses are adjusted (rescaled) to common values, and known correlations are taken into account. The averages include branching fractions, lifetimes, neutral meson mixing parameters, C P violation parameters, parameters of semileptonic decays, and Cabibbo–Kobayashi–Maskawa matrix elements

    Observation of the diphoton decay of the Higgs boson and measurement of its properties

    Get PDF
    Peer reviewe

    Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at √s=8 Tev

    Get PDF
    Peer reviewe

    Study of double parton scattering using W+2-jet events in proton-proton collisions at √s=7 TeV

    Get PDF
    Peer reviewe

    Observation of Two New Excited Ξb0 States Decaying to Λb0 K-π+

    Get PDF
    Two narrow resonant states are observed in the Λb0K-π+ mass spectrum using a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6 fb-1. The minimal quark content of the Λb0K-π+ system indicates that these are excited Ξb0 baryons. The masses of the Ξb(6327)0 and Ξb(6333)0 states are m[Ξb(6327)0]=6327.28-0.21+0.23±0.12±0.24 and m[Ξb(6333)0]=6332.69-0.18+0.17±0.03±0.22 MeV, respectively, with a mass splitting of Δm=5.41-0.27+0.26±0.12 MeV, where the uncertainties are statistical, systematic, and due to the Λb0 mass measurement. The measured natural widths of these states are consistent with zero, with upper limits of Γ[Ξb(6327)0]<2.20(2.56) and Γ[Ξb(6333)0]<1.60(1.92) MeV at a 90% (95%) credibility level. The significance of the two-peak hypothesis is larger than nine (five) Gaussian standard deviations compared to the no-peak (one-peak) hypothesis. The masses, widths, and resonant structure of the new states are in good agreement with the expectations for a doublet of 1D Ξb0 resonances

    Measurement of Higgs boson production and properties in the WW decay channel with leptonic final states

    Get PDF
    Peer reviewe

    Measurements of the tt¯ charge asymmetry using the dilepton decay channel in pp collisions at √s=7 TeV

    Get PDF
    Peer reviewe

    Searches for new physics using the t(t)over-bar invariant mass distribution in pp collisions at √s=8 TeV

    Get PDF
    This is the pre-print version of the final published paper that is available from the link belowSearches for anomalous top quark-antiquark production are presented, based on pp collisions at √s=8  TeV . The data, corresponding to an integrated luminosity of 19:7 fb^-1, were collected with the CMS detector at the LHC. The observed tt invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements

    Measurement of associated production of vector bosons and top quark-antiquark pairs in pp collisions at √s=7 TeV

    Get PDF
    PubMed ID: 23679709The first measurement of vector-boson production associated with a top quark-antiquark pair in proton-proton collisions at s √ =7  TeV is presented. The results are based on a data set corresponding to an integrated luminosity of 5.0  fb^−1 , recorded by the CMS detector at the LHC in 2011. The measurement is performed in two independent channels through a trilepton analysis of tt ¯ Z events and a same-sign dilepton analysis of tt ¯ V (V=W or Z ) events. In the trilepton channel a direct measurement of the tt ¯ Z cross section σ tt ¯ Z =0.28 [+0.14 −0.11]  (stat) [+0.06 −0.03]  (syst)  pb is obtained. In the dilepton channel a measurement of the tt ¯ V cross section yields σtt¯V=0.43 [+0.17 −0.15]  (stat) [+0.09 −0.07]  (syst)  pb . These measurements have a significance, respectively, of 3.3 and 3.0 standard deviations from the background hypotheses and are compatible, within uncertainties, with the corresponding next-to-leading order predictions of 0.137[+0.012 −0.016] and 0.306 [+0.031 −0.053]   pb
    corecore