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Measurement of differential top-quark-pair production cross sections in pp collisions at √s =7 TeV
(2013)The European Physical Journal CNormalised differential top-quark-pair production cross sections are measured in pp collisions at a centre-of-mass energy of 7 TeVat the LHC with the CMS detector using data recorded in 2011 corresponding to an integrated luminosity of 5.0 fb−1. The measurements are performed in the lepton+jets decay channels (e+jets and μ+jets) and the dilepton decay channels (e+e−, μ + μ −, and μ ±e∓). The tt¯ differential cross section is measured as ...Journal Article -
Search for a narrow, spin-2 resonance decaying to a pair of Z bosons in the qq¯ℓ+ℓ− final state
(2013)Physics Letters BResults are presented from a search for a narrow, spin-2 resonance decaying into a pair of Z bosons, with one Z-boson decaying into leptons (e+e− or μ+μ−) and the other into jets. An example of such a resonance is the Kaluza–Klein graviton, GKK, predicted in Randall–Sundrum models. The analysis is based on a 4.9 fb−1 sample of proton–proton collisions at a center-of-mass energy of 7 TeV, collected with the CMS detector at the LHC. Kinematic ...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 long-lived particles in events with photons and missing energy in proton–proton collisions at √s=7 TeV
(2013)Physics Letters BResults are presented from a search for long-lived neutralinos decaying into a photon and an invisible particle, a signature associated with gauge-mediated supersymmetry breaking in supersymmetric models. The analysis is based on a 4.9fb−1 sample of proton-proton collisions at s=7TeV, collected with the CMS detector at the LHC. The missing transverse energy and the time of arrival of the photon at the electromagnetic calorimeter are used ...Journal Article -
Search for heavy resonances in the W/Z-tagged dijet mass spectrum in pp collisions at 7 TeV
(2013)Physics Letters BA search has been made for massive resonances decaying into a quark and a vector boson, qW or qZ, or a pair of vector bosons, WW, WZ, or ZZ, where each vector boson decays to hadronic final states. This search is based on a data sample corresponding to an integrated luminosity of 5.0 fb-1 of proton-proton collisions collected in the CMS experiment at the LHC in 2011 at a center-of-mass energy of 7 TeV. For sufficiently heavy resonances ...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 -
Search for a non-standard-model Higgs boson decaying to a pair of new light bosons in four-muon final states
(2013)Physics Letters BResults are reported from a search for non-standard-model Higgs boson decays to pairs of new light bosons, each of which decays into the μ+μ- final state. The new bosons may be produced either promptly or via a decay chain. The data set corresponds to an integrated luminosity of 5.3 fb-1 of proton-proton collisions at s=7 TeV, recorded by the CMS experiment at the LHC in 2011. Such Higgs boson decays are predicted in several scenarios of ...Journal Article -
Search for heavy narrow dilepton resonances in pp collisions at √s=7 TeV and √s=8 TeV
(2013)Physics Letters BAn updated search for heavy narrow resonances decaying to muon or electron pairs using the CMS detector is presented. Data samples from pp collisions at s=7TeV and 8 TeV at the LHC, with integrated luminosities of up to 5.3 and 4.1fb−1, respectively, are combined. No evidence for a heavy narrow resonance is observed. The analysis of the combined data sets excludes, at 95% confidence level, a Sequential Standard Model ZSSM′ resonance lighter ...Journal Article -
Measurement of W+W- and ZZ production cross sections in pp collisions at sqrt(s) = 8 TeV
(2013)Physics Letters BThe W+W- and ZZ production cross sections are measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC in data samples corresponding to an integrated luminosity of up to 5.3 fb(-1). The measurements are performed in the leptonic decay modes W+W- -> l'vl '' v and ZZ -> 2l2l', where l = e, mu and l'(l '') = e, mu, tau. The measured cross sections sigma (pp -> W+W-) =, 69.9 +/- 2.8 (stat.) +/- 5.6 (syst.) 3.1 ...Journal Article