Search
Results
-
Studies of dijet transverse momentum balance and pseudorapidity distributions in pPb collisions at √sNN = 5.02 TeV
(2014)The European Physical Journal CDijet production has been measured in pPb collisions at a nucleon–nucleon centre-of-mass energy of 5.02TeV. A data sample corresponding to an integrated luminosity of 35 nb−1 was collected using the Compact Muon Solenoid detector at the Large Hadron Collider. The dijet transverse momentum balance, azimuthal angle correlations, and pseudorapidity distributions are studied as a function of the transverse energy in the forward calorimeters ...Journal Article -
Search for Flavor-Changing Neutral Currents in Top-Quark Decays t→Zq in pp Collisions at √s = 8 TeV
(2014)Physical Review LettersA search for flavor-changing neutral currents in top-quark decays t → Zq is performed in events produced from the decay chain t¯t → Zq + Wb, where both vector bosons decay leptonically, producing a final state with three leptons (electrons or muons). A data set collected with the CMS detector at the LHC is used, corresponding to an integrated luminosity of 19.7 fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. No excess ...Journal Article -
Search for Top-Quark Partners with Charge 5/3 in the Same-Sign Dilepton Final State
(2014)Physical Review LettersA search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5fb−1 and was collected at √s = 8 TeV by the CMS experiment. No significant excess is observed in the data above the expected background, and the existence of top-quark partners with masses below 800 GeV is excluded at a 95% confidence level, ...Journal Article -
Observation of a peaking structure in the J/ψφ mass spectrum from B±→J/ψφK± decays
(2014)Physics Letters BA peaking structure in the J/ψφ mass spectrum near threshold is observed in B ±→J/ψφK± decays, produced in pp collisions at √s=7 TeV collected with the CMS detector at the LHC. The data sample, selected on the basis of the dimuon decay mode of the J/ψ, corresponds to an integrated luminosity of 5.2 fb-1. Fitting the structure to an S-wave relativistic Breit-Wigner lineshape above a three-body phase-space nonresonant component gives a ...Journal Article -
Measurement of the production cross section for a W boson and two b jets in pp collisions at √s=7 TeV
(2014)Physics Letters BThe production cross section for a W boson and two b jets is measured using proton-proton collisions at √s=7 TeV in a data sample collected with the CMS experiment at the LHC corresponding to an integrated luminosity of 5.0 fb-1. The W+bb- events are selected in the W→μν decay mode by requiring a muon with transverse momentum pT > 25 GeV and pseudorapidity |η| < 2.1, and exactly two b-tagged jets with pT > 25 GeV and |η| < 2.4. The measured ...Journal Article -
Measurement of the top-quark mass in all-jets tt events in pp collisions at √s = 7 TeV
(2014)The European Physical Journal CThe mass of the top quark is measured using a sample of tt¯ candidate events with at least six jets in the final state. The sample is selected from data collected with the CMS detector in pp collisions at s√=7 TeV in 2011 and corresponds to an integrated luminosity of 3.54 fb−1. The mass is reconstructed for each event employing a kinematic fit of the jets to a tt¯ hypothesis. The top-quark mass is measured to be 173.49±0.69(stat.)±1.21(syst.) ...Journal Article -
Probing color coherence effects in pp collisions at √s = 7 TeV
(2014)The European Physical Journal CA study of color coherence effects in pp collisions at a center-of-mass energy of 7TeV is presented. The data used in the analysis were collected in 2010 with the CMS detector at the LHC and correspond to an integrated luminosity of 36 pb−1. Events are selected that contain at least three jets and where the two jets with the largest transverse momentum exhibit a back-to-back topology. The measured angular correlation between the second- ...Journal Article -
Study of the production of charged pions, kaons, and protons in pPb collisions at √sNN = 5.02 TeV
(2014)The European Physical Journal CSpectra of identified charged hadrons are measured in pPb collisions with the CMS detector at the LHC at sNN−−−−√=5.02TeV. Charged pions, kaons, and protons in the transverse-momentum range pT≈0.1–1.7GeV/c and laboratory rapidity |y|<1 are identified via their energy loss in the silicon tracker. The average pT increases with particle mass and the charged multiplicity of the event. The increase of the average pT with charged multiplicity ...Journal Article -
Determination of the top-quark pole mass and strong coupling constant from the tt¯ production cross section in pp collisions at √s = 7 TeV
(2014)Physics Letters BThe inclusive cross section for top-quark pair production measured by the CMS experiment in proton–proton collisions at a center-of-mass energy of 7 TeV is compared to the QCD prediction at next-to-next-to-leading order with various parton distribution functions to determine the top-quark pole mass, mt pole, or the strong coupling constant, αS. With the parton distribution function set NNPDF2.3, a pole mass of 176.7−3.4 +3.8 GeV is obtained ...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