Search
Results
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Search for electroweak production of charginos and neutralinos using leptonic final states in pp collisions at √s=7 TeV
(2012)Journal of High Energy PhysicsThe 2011 dataset of the CMS experiment, consisting of an integrated luminosity of 4.98 fb−1 of pp collisions at s√=7 TeV, enables expanded searches for direct electroweak pair production of charginos and neutralinos in supersymmetric models as well as their analogs in other models of new physics. Searches sensitive to such processes, with decays to final states that contain two or more leptons, are presented. Final states with three ...Journal Article -
Search for stopped long-lived particles produced in pp collisions at √s=7TeV
(2012)Journal of High Energy PhysicsA search has been performed for long-lived particles that have stopped in the CMS detector, during 7 TeV proton-proton operations of the CERN LHC. The existence of such particles could be inferred from observation of their decays when there were no proton-proton collisions in the CMS detector, namely during gaps between LHC beam crossings. Using a data set in which CMS recorded an integrated luminosity of 4.0 fb−1, and a search interval ...Journal Article -
Measurement of the Pseudorapidity and Centrality Dependence of the Transverse Energy Density in Pb-Pb Collisions at √sNN=2.76 TeV
(2012)Physical Review LettersThe transverse energy (ET) in Pb-Pb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (√sNN) has been measured over a broad range of pseudorapidity (η) and collision centrality by using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dET/dη) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision ...Journal Article -
Measurement of the underlying event activity in pp collisions at √s=0.9 and 7 TeV with the novel jet-area/median approach
(2012)Journal of High Energy PhysicsThe first measurement of the charged component of the underlying event using the novel “jet-area/median” approach is presented for proton-proton collisions at centre-of-mass energies of 0.9 and 7 TeV. The data were recorded in 2010 with the CMS experiment at the LHC. A new observable, sensitive to soft particle production, is introduced and investigated inclusively and as a function of the event scale defined by the transverse momentum ...Journal Article -
Search for new physics with long-lived particles decaying to photons and missing energy in pp collisions at √s=7 TeV
(2012)Journal of High Energy PhysicsA search is performed for long-lived neutral particles decaying into a photon and invisible particles. An example of such a signature is the decay of the lightest neutralino with nonzero lifetime into a gravitino and a photon in gauge-mediated supersymmetry, with the neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest. The search uses events containing photons, missing transverse energy, and jets. ...Journal Article -
Search for the standard model Higgs boson produced in association with W and Z bosons in pp collisions at √s=7 TeV
(2012)Journal of High Energy PhysicsA search for the Higgs boson produced in association with a W or Z boson in proton-proton collisions at a center-of-mass energy of 7 TeV is performed with the CMS detector at the LHC using the full 2011 data sample, from an integrated luminosity of 5 fb−1. Higgs boson decay modes to ττ and WW are explored by selecting events with three or four leptons in the final state. No excess above background expectations is observed, resulting in ...Journal Article -
Observation of Z decays to four leptons with the CMS detector at the LHC
(2012)Journal of High Energy PhysicsThe first observation of the Z boson decaying to four leptons in proton-proton collisions is presented. The analyzed data set corresponds to an integrated luminosity of 5.02 fb−1 at s√=7 TeV collected by the CMS detector at the Large Hadron Collider. A pronounced resonance peak, with a statistical significance of 9.7 σ, is observed in the distribution of the invariant mass of four leptons (electrons and/or muons) with mass and width ...Journal Article -
Search for a light charged Higgs boson in top quark decays in pp collisions at √s=7TeV
(2012)Journal of High Energy PhysicsResults are presented on a search for a light charged Higgs boson that can be produced in the decay of the top quark t → H+b and which, in turn, decays into τ +ν τ . The analysed data correspond to an integrated luminosity of about 2 fb−1 recorded in protonproton collisions at s√=7TeV by the CMS experiment at the LHC. The search is sensitive to the decays of the top quark pairs tt¯ → H± W ∓ bb¯¯¯ and tt¯ → H±H∓ bb¯¯¯. Various final states ...Journal Article -
Search for third-generation leptoquarks and scalar bottom quarks in pp collisions at √s=7TeV
(2012)Journal of High Energy PhysicsResults are presented from a search for third-generation leptoquarks and scalar bottom quarks in a sample of proton-proton collisions at s√=7TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.7 fb−1. A scenario where the new particles are pair produced and each decays to a b quark plus a tau neutrino or neutralino is considered. The number of observed events is found to be in agreement with the ...Journal Article -
Measurement of the mass difference between top and antitop quarks
(2012)Journal of High Energy PhysicsA measurement of the mass difference between the top and the antitop quark (Δm t = m t − mt¯) is performed using events with a muon or an electron and at least four jets in the final state. The analysis is based on data collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 4.96±0.11 fb−1, and yields the value of Δm t = −0.44±0.46 (stat.)±0.27 (syst.) GeV. This result is consistent with equality of particle ...Journal Article