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Measurement of the ratio B(t→Wb)/B(t→Wq) in pp collisions at √s = 8 TeV
(2014)Physics Letters BThe ratio of the top-quark branching fractions R = B(t --> Wb)/B(t --> Wq), where the denominator includes the sum over all down-type quarks (q = b, s, d), is measured in the t (t) over bar dilepton final state with proton-proton collision data at root s = 8 TeV from an integrated luminosity of 19.7 fb(-1), collected with the CMS detector. In order to quantify the purity of the signal sample, the cross section is measured by fitting the ...Journal Article -
Search for single production of a vector-like T quark decaying to a Z boson and a top quark in proton-proton collisions at s = 13 TeV
(2018)Physics letters BA search is presented for single production of a vector-like quark (T) decaying to a Z boson and a top quark, with the Z boson decaying leptonically and the top quark decaying hadronically. The search uses data collected by the CMS experiment in proton–proton collisions at a center-of-mass energy of 13 TeV in 2016, corresponding to an integrated luminosity of 35.9 fb-1. The presence of forward jets is a particular characteristic of single ...Journal Article -
Impact of low-dose electron irradiation on n+p silicon strip sensors
(2015)Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated EquipmentThe response of n+p silicon strip sensors to electrons from a 90Sr source was measured using a multi-channel read-out system with 25 ns sampling time. The measurements were performed over a period of several weeks, during which the operating conditions were varied. The sensors were fabricated by Hamamatsu Photonics on 200 μm thick float-zone and magnetic-Czochralski silicon. Their pitch was 80 μm, and both p-stop and p-spray isolation of ...Journal Article -
Search for Monotop Signatures in Proton-Proton Collisions at √s=8 TeV
(2015)Physical Review LettersResults are presented from a search for new decaying massive particles whose presence is inferred from an imbalance in transverse momentum and which are produced in association with a single top quark that decays into a bottom quark and two light quarks. The measurement is performed using 19.7 fb−1 of data from proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No deviations ...Journal Article -
Search for Narrow Resonances in Dijet Final States at √s=8 TeV with the Novel CMS Technique of Data Scouting
(2016)Physical Review LettersA search for narrow resonances decaying into dijet final states is performed on data from proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 18.8 fb−1. The data were collected with the CMS detector using a novel technique called data scouting, in which the information associated with these selected events is much reduced, permitting collection of larger data samples. This technique ...Journal Article -
Evidence for Collective Multiparticle Correlations in p-Pb Collisions
(2015)Physical Review LettersThe second-order azimuthal anisotropy Fourier harmonics, v2, are obtained in p−Pb and PbPb collisions over a wide pseudorapidity (η) range based on correlations among six or more charged particles. The p-Pb data, corresponding to an integrated luminosity of 35 nb−1, were collected during the 2013 LHC p-Pb run at a nucleon-nucleon center-of-mass energy of 5.02 TeV by the CMS experiment. A sample of semiperipheral PbPb collision data at ...Journal Article -
Study of the Mass and Spin-Parity of the Higgs Boson Candidate via Its Decays to Z Boson Pairs
(2013)Physical Review LettersA study is presented of the mass and spin-parity of the new boson recently observed at the LHC at a mass near 125 GeV. An integrated luminosity of 17.3 fb−1, collected by the CMS experiment in proton-proton collisions at center-of-mass energies of 7 and 8 TeV, is used. The measured mass in the ZZ channel, where both Z bosons decay to e or μ pairs, is 126.2±0.6(stat)±0.2(syst) GeV. The angular distributions of the lepton pairs in this ...Journal Article -
Multiplicity and transverse momentum dependence of two- and four-particle correlations in pPb and PbPb collisions
(2013)Physics Letters BMeasurements of two- and four-particle angular correlations for charged particles emitted in pPb collisions are presented over a wide range in pseudorapidity and full azimuth. The data, corresponding to an integrated luminosity of approximately 31nb-1, were collected during the 2013 LHC pPb run at a nucleon-nucleon center-of-mass energy of 5.02 TeV by the CMS experiment. The results are compared to 2.76 TeV semi-peripheral PbPb collision ...Journal Article -
Search for a standard model Higgs boson produced in association with a top-quark pair and decaying to bottom quarks using a matrix element method
(2015)The European Physical Journal CA search for a standard model Higgs boson produced in association with a top-quark pair and decaying to bottom quarks is presented. Events with hadronic jets and one or two oppositely charged leptons are selected from a data sample corresponding to an integrated luminosity of 19.5fb-1 collected by the CMS experiment at the LHC in pp collisions at a centre-of-mass energy of 8TeV. In order to separate the signal from the larger tt¯ + jets ...Journal Article -
Angular analysis and branching fraction measurement of the decay B0→K*0μ+μ-
(2013)Physics Letters BThe angular distributions and the differential branching fraction of the decay B0→K*(892)0μ+μ- are studied using a data sample corresponding to an integrated luminosity of 5.2fb-1 collected with the CMS detector at the LHC in pp collisions at s=7TeV. From more than 400 signal decays, the forward-backward asymmetry of the muons, the K*(892)0 longitudinal polarization fraction, and the differential branching fraction are determined as a ...Journal Article