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Description and performance of track and primary-vertex reconstruction with the CMS tracker akahashi
(2014)Journal of InstrumentationA description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tbar t events ...Journal Article -
Search for WWγ and WZγ production and constraints on anomalous quartic gauge couplings in pp collisions at √s=8 TeV
(2014)Physical Review DA search for WVγ triple vector boson production is presented based on events containing a W boson decaying to a muon or an electron and a neutrino, a second V (W or Z) boson, and a photon. The data correspond to an integrated luminosity of 19.3 fb−1 collected in 2012 with the CMS detector at the LHC in pp collisions at √s=8 TeV. An upper limit of 311 fb on the cross section for the WVγ production process is obtained at 95% confidence ...Journal Article -
Measurement of Prompt ψ(2S) to J/ψ Yield Ratios in Pb-Pb and p-p Collisions at √sNN = 2.76 TeV
(2014)Physical Review LettersThe ratio between the prompt ψ(2S) and J/ψ yields, reconstructed via their decays into μ+μ−, is measured in Pb-Pb and p-p collisions at √sNN=2.76 TeV. The analysis is based on Pb-Pb and p-p data samples collected by CMS at the Large Hadron Collider, corresponding to integrated luminosities of 150 μb−1 and 5.4 pb−1, respectively. The double ratio of measured yields (Nψ(2S)/NJ/ψ)Pb−Pb/(Nψ(2S)/NJ/ψ)p−p is computed in three Pb-Pb collision ...Journal Article -
Measurement of four-jet production in proton-proton collisions at √s =7TeV
(2014)Physical Review DMeasurements of the differential cross sections for the production of exactly four jets in proton-proton collisions are presented as a function of the transverse momentum pT and pseudorapidity η, together with the correlations in azimuthal angle and the pT balance among the jets. The data sample was collected in 2010 at a center-of-mass energy of 7 TeV with the CMS detector at the LHC, with an integrated luminosity of 36 pb−1. The cross ...Journal Article -
Measurements of t¯t Spin Correlations and Top-Quark Polarization Using Dilepton Final States in pp Collisions at √s=7 TeV
(2014)Physical Review LettersSpin correlations and polarization in the top quark–antiquark system are measured using dilepton final states produced in pp collisions at the LHC at √s=7 TeV. The data correspond to an integrated luminosity of 5.0 fb−1 collected with the CMS detector. The measurements are performed using events with two oppositely charged leptons (electrons or muons), a significant imbalance in transverse momentum, and two or more jets, where at least ...Journal Article -
Measurement of the muon charge asymmetry in inclusive pp→W+X production at √s = 7 Tev and an improved determination of light parton distribution functions
(2014)Physical Review DMeasurements of the muon charge asymmetry in inclusive pp→W+X production at √s=7 TeV are presented. The data sample corresponds to an integrated luminosity of 4.7 fb−1 recorded with the CMS detector at the LHC. With a sample of more than 20 million W→μν events, the statistical precision is greatly improved in comparison to previous measurements. These new results provide additional constraints on the parton distribution functions of the ...Journal Article -
Searches for electroweak neutralino and chargino production in channels with Higgs, Z, and W bosons in pp collisions at 8 TeV
(2014)Physical Review DSearches for supersymmetry (SUSY) are presented based on the electroweak pair production of neutralinos and charginos, leading to decay channels with Higgs, Z, and W bosons and undetected lightest SUSY particles (LSPs). The data sample corresponds to an integrated luminosity of about 19.5 fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV collected in 2012 with the CMS detector at the LHC. The main emphasis is neutralino ...Journal Article