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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 -
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 -
Search for anomalous production of events with three or more leptons in pp collisions at √s = 8 TeV
(2014)Physical Review DA search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5 fb−1 of proton-proton collisions with center-of-mass energy √s = 8 TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, ...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 -
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 -
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 WZ and ZZ production in pp collisions at √s = 8TeV in final states with b-tagged jets
(2014)The European Physical Journal CMeasurements are reported of the WZ and ZZ production cross sections in proton-proton collisions at s√=8 TeV in final states where one Z boson decays to b-tagged jets. The other gauge boson, either W or Z, is detected through its leptonic decay (either W→eν, μν or Z→e+e−, μ+μ−, or νν¯¯¯). The results are based on data corresponding to an integrated luminosity of 18.9 fb−1 collected with the CMS detector at the Large Hadron Collider. The ...Journal Article -
Search for pair production of third-generation scalar leptoquarks and top squarks in proton-proton collisions at √s = 8 TeV
(2014)Physics Letters BA search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton–proton collisions corresponding to an integrated luminosity of 19.7 fb−1, collected with the CMS detector at the LHC with s=8 TeV. The number of observed events is found to be in agreement with the ...Journal Article -
Searches for electroweak production of charginos, neutralinos, and sleptons decaying to leptons and W, Z, and Higgs bosons in pp collisions at 8 TeV
(2014)The European Physical Journal CSearches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and W, Z, and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy s√=8TeV with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5 fb-1. The observed event rates are in agreement with expectations from ...Journal Article