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Measurement of the underlying event in the Drell–Yan process in proton–proton collisions at √s = 7 TeV
(2012)The European Physical Journal CA measurement of the underlying event (UE) activity in proton–proton collisions at a center-of-mass energy of 7 TeV is performed using Drell–Yan events in a data sample corresponding to an integrated luminosity of 2.2 fb−1, collected by the CMS experiment at the LHC. The activity measured in the muonic final state (qq¯¯¯→μ+μ−) is corrected to the particle level and compared with the predictions of various Monte Carlo generators and ...Journal Article -
Measurement of isolated photon production in pp and PbPb collisions at root s(NN)=2.76 TeV
(2012)Physics Letters BIsolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |η|<1.44 and transverse energies E T between 20 and 80 GeV with the CMS detector at the LHC. The measured E T spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon E T-differential yields, ...Journal Article -
Study of high-pT charged particle suppression in PbPb compared to pp collisions at √sNN=2.76 TeV
(2012)The European Physical Journal CThe transverse momentum spectra of charged particles have been measured in pp and PbPb collisions at sNN−−−−√=2.76 TeV by the CMS experiment at the LHC. In the transverse momentum range p T=5–10 GeV/c, the charged particle yield in the most central PbPb collisions is suppressed by up to a factor of 7 compared to the pp yield scaled by the number of incoherent nucleon–nucleon collisions. At higher p T, this suppression is significantly ...Journal Article -
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 -
Study of the inclusive production of charged pions, kaons, and protons in pp collisions at √s=0.9, 2.76, and 7 TeV
(2012)The European Physical Journal CSpectra of identified charged hadrons are measured in pp collisions at the LHC for s√=0.9,2.76, and 7 TeV. Charged pions, kaons, and protons in the transverse-momentum range p T≈0.1–1.7 GeV/c and for rapidities |y|<1 are identified via their energy loss in the CMS silicon tracker. The average p T increases rapidly with the mass of the hadron and the event charged-particle multiplicity, independently of the center-of-mass energy. The fully ...Journal Article -
Search for neutral Higgs bosons decaying to tau pairs in pp collisions at sqrt(s)=7 TeV
(2012)Physics Letters BA search for neutral Higgs bosons decaying to tau pairs at a center-of-mass energy of 7 TeV is performed using a dataset corresponding to an integrated luminosity of 4.6 fb−1 recorded by the CMS experiment at the LHC. The search is sensitive to both the standard model Higgs boson and to the neutral Higgs bosons predicted by the minimal supersymmetric extension of the standard model (MSSM). No excess of events is observed in the tau-pair ...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 -
Search for Neutral Minimal Supersymmetric Standard Model Higgs Bosons Decaying to Tau Pairs in pp Collisions at √s=7 TeV
(2011)Physical Review LettersA search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb−1 recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs ...Journal Article -
Search for Pair Production of Second-Generation Scalar Leptoquarks in pp Collisions at √s=7 TeV
(2011)Physical Review LettersA search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at √s=7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb−1. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation ...Journal Article -
Measurement of Dijet Angular Distributions and Search for Quark Compositeness in pp Collisions √s=7 TeV
(2011)Physical Review LettersDijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at √s=7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb−1. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction ...Journal Article