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Measurement of the tt¯ production cross section in pp collisions at √s=8 TeV in dilepton final states containing one τ lepton
(2014)Physics Letters BThe top-quark pair production cross section is measured in final states with one electron or muon and one hadronically decaying τ lepton from the process tt→(ℓνℓ)(τντ)bb-, where ℓ=e,μ. The data sample corresponds to an integrated luminosity of 19.6 fb-1 collected with the CMS detector in proton-proton collisions at √s=8 TeV. The measured cross section σtt-=257±3 (stat)±24 (syst)±7 (lumi) pb, assuming a top-quark mass of 172.5 GeV, is ...Journal Article -
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 -
Modification of jet shapes in PbPb collisions at sNN=2.76TeV
(2014)Physics Letters BThe first measurement of jet shapes, defined as the fractional transverse momentum radial distribution, for inclusive jets produced in heavy-ion collisions is presented. Data samples of PbPb and pp collisions, corresponding to integrated luminosities of 150 mu b(-1) and 5.3 pb(-1) respectively, were collected at a nucleon-nucleon centre-of-mass energy of root s(NN) = 2.76 TeV with the CMS detector at the LHC. The jets are reconstructed ...Journal Article -
Search for excited quarks in the γ+jet final state in proton–proton collisions at √s=8 TeV
(2014)Physics Letters BA search for excited quarks decaying into the γ+jet final state is presented. The analysis is based on data corresponding to an integrated luminosity of 19.7fb−1collected by the CMS experiment in proton-proton collisions at s=8 TeV at the LHC. Events with photons and jets with high transverse momenta are selected and the γ+jet invariant mass distribution is studied to search for a resonance peak. The 95% confidence level upper limits on ...Journal Article -
Evidence of b -Jet Quenching in PbPb Collisions at √sNN =2.76 TeV
(2014)Physical Review LettersThe production of jets associated to bottom quarks is measured for the first time in PbPb collisions at a center-of-mass energy of 2.76 TeV per nucleon pair. Jet spectra are reported in the transverse momentum (pT) range of 80-250GeV/c, and within pseudorapidity |η|<2. The nuclear modification factor (RAA) calculated from these spectra shows a strong suppression in the b-jet yield in PbPb collisions relative to the yield observed in pp ...Journal Article -
Observation of the associated production of a single top quark and a W Boson in pp collisions at √s = 8 TeV
(2014)Physical Review LettersJournal Article -
Searches for light- and heavy-flavour three-jet resonances in pp collisions at √s=8TeV
(2014)Physics Letters BA search for three-jet hadronic resonance production in pp collisions at a centre-of-mass energy of 8 TeV has been conducted by the CMS Collaboration at the LHC with a data sample corresponding to an integrated luminosity of 19.4 fb(-1). The search method is model independent, and events are selected that have high jet multiplicity and large values of jet transverse momenta. The signal models explored assume R-parity-violating supersymmetric ...Journal Article -
Search for supersymmetry in pp collisions at √s= 8 TeV in events with a single lepton, large jet multiplicity, and multiple b jets
(2014)Physics Letters BResults are reported from a search for supersymmetry in pp collisions at a center-of-mass energy of 8 TeV, based on events with a single isolated lepton (electron or muon) and multiple jets, at least two of which are identified as b jets. The data sample corresponds to an integrated luminosity of 19.3 fb(-1) recorded by the CMS experiment at the LHC in 2012. The search is motivated by supersymmetric models that involve strong-production ...Journal Article -
Search for baryon number violation in top-quark decays
(2014)Physics Letters BA search for baryon number violation (BNV) in top-quark decays is performed using pp collisions produced by the LHC at s=8 TeV. The top-quark decay considered in this search results in one light lepton (muon or electron), two jets, but no neutrino in the final state. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.5 fb-1. The event selection is optimized for top quarks produced ...Journal Article -
Constraints on the Higgs boson width from off-shell production and decay to Z-boson pairs
(2014)Physics Letters BConstraints are presented on the total width of the recently discovered Higgs boson, ΓH, using its relative on-shell and off-shell production and decay rates to a pair of Z bosons, where one Z boson decays to an electron or muon pair, and the other to an electron, muon, or neutrino pair. The analysis is based on the data collected by the CMS experiment at the LHC in 2011 and 2012, corresponding to integrated luminosities of 5.1fb -1 at a ...Journal Article