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Measurements of the p p → Z Z production cross section and the Z → 4 ℓ branching fraction, and constraints on anomalous triple gauge couplings at √s=13TeV
(2018)The European Physical Journal CFour-lepton production in proton-proton collisions, pp→(Z/γ∗)(Z/γ∗)→4ℓ, where ℓ=e or μ, is studied at a center-of-mass energy of 13TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9fb−1. The ZZ production cross section, σ(pp→ZZ)=17.2±0.5(stat)±0.7(syst)±0.4(theo)±0.4(lumi) pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60<mℓ+ℓ−<120GeV, ...Journal Article -
Search for pair production of excited top quarks in the lepton + jets final state
(2018)Physics Letters BA search is performed for the pair production of spin-3/2 excited top quarks, each decaying to a top quark and a gluon. The search uses the data collected with the CMS detector from proton–proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9fb-1. Events are selected by requiring an isolated muon or electron, an imbalance in the transverse momentum, and at least six jets of which exactly ...Journal Article -
Search for Higgs boson pair production in events with two bottom quarks and two tau leptons in proton-proton collisions at √s=13 TeV
(2018)Physics Letters BA search for the production of Higgs boson pairs in proton–proton collisions at a centre-of-mass energy of 13 TeV is presented, using a data sample corresponding to an integrated luminosity of 35.9 fb-1 collected with the CMS detector at the LHC. Events with one Higgs boson decaying into two bottom quarks and the other decaying into two τ leptons are explored to investigate both resonant and nonresonant production mechanisms. The data are ...Journal Article -
Azimuthal anisotropy of charged particles with transverse momentum up to 100 GeV/ c in PbPb collisions at √sNN=5.02 TeV
(2018)Physics Letters BThe Fourier coefficients v2 and v3 characterizing the anisotropy of the azimuthal distribution of charged particles produced in PbPb collisions at sNN=5.02 TeV are measured with data collected by the CMS experiment. The measurements cover a broad transverse momentum range, 1<pT<100 GeV/c. The analysis focuses on the pT>10 GeV/c range, where anisotropic azimuthal distributions should reflect the path-length dependence of parton energy loss ...Journal Article -
Measurements of tt¯ cross sections in association with b jets and inclusive jets and their ratio using dilepton final states in pp collisions at s√ = 13 TeV
(2018)Physics Letters BThe cross sections for the production of tt¯bb¯ and tt¯jj events and their ratio σtt¯bb¯/σtt¯jj are measured using data corresponding to an integrated luminosity of 2.3 fb−1collected in pp collisions at s=13 TeV with the CMS detector at the LHC. Events with two leptons (e or μ) and at least four reconstructed jets, including at least two identified as b quark jets, in the final state are selected. In the full phase space, the measured ...Journal Article -
Search for lepton flavour violating decays of the Higgs boson to μτ and eτ in proton-proton collisions at √s=13 TeV
(2018)Journal of High Energy PhysicsA search for lepton flavour violating decays of the Higgs boson in the μτ and eτ decay modes is presented. The search is based on a data set corresponding to an integrated luminosity of 35.9 fb−1 of proton-proton collisions collected with the CMS detector in 2016, at a centre-of-mass energy of 13 TeV. No significant excess over the standard model expectation is observed. The observed (expected) upper limits on the lepton flavour violating ...Journal Article -
Measurement of associated Z + charm production in proton–proton collisions at √s=8TeV
(2018)The European Physical Journal CA study of the associated production of a Z boson and a charm quark jet (Z+c), and a comparison to production with a b quark jet (Z+b), in pp collisions at a centre-of-mass energy of 8TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7fb−1, collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets ...Journal Article -
Search for standard model production of four top quarks with same-sign and multilepton final states in proton–proton collisions at √s=13TeV
(2018)The European Physical Journal CA search for standard model production of four top quarks (tt¯tt¯) is reported using events containing at least three leptons (e,μ) or a same-sign lepton pair. The events are produced in proton–proton collisions at a center-of-mass energy of 13TeV at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9fb−1. Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control ...Journal Article -
Comparing transverse momentum balance of b jet pairs in pp and PbPb collisions at root s(NN)=5.02 TeV
(2018)Journal of High Energy PhysicsThe transverse momentum balance of pairs of back-to-back b quark jets in PbPb and pp collisions recorded with the CMS detector at the LHC is reported. The center-of-mass energy in both collision systems is 5.02 TeV per nucleon pair. Compared to the pp collision baseline, b quark jets have a larger imbalance in the most central PbPb collisions, as expected from the jet quenching effect. The data are also compared to the corresponding ...Journal Article -
Search for natural supersymmetry in events with top quark pairs and photons in pp collisions at root s=8 TeV
(2018)Journal of High Energy PhysicsResults are presented from a search for natural gauge-mediated supersymmetry (SUSY) in a scenario in which the top squark is the lightest squark, the next-to-lightest SUSY particle is a bino-like neutralino, and the lightest SUSY particle is the gravitino. The strong production of top squark pairs can produce events with pairs of top quarks and neutralinos, with each bino-like neutralino decaying to a photon and a gravitino. The search ...Journal Article