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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 -
Study of dijet events with a large rapidity gap between the two leading jets in pp collisions at √s=7TeV
(2018)The European Physical Journal CEvents with no charged particles produced between the two leading jets are studied in proton-proton collisions at s√=7 TeV. The jets were required to have transverse momentum pjetT>40 GeV and pseudorapidity 1.5<|ηjet|<4.7, and to have values of ηjet with opposite signs. The data used for this study were collected with the CMS detector during low-luminosity running at the LHC, and correspond to an integrated luminosity of 8pb−1. Events ...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 -
Search for physics beyond the standard model in final states with a lepton and missing transverse energy in proton-proton collisions at √s = 8 TeV
(2015)Physical Review DA search for new physics in proton-proton collisions having final states with an electron or muon and missing transverse energy is presented. The analysis uses data collected in 2012 with the CMS detector, at an LHC center-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of 19.7 fb−1. No significant deviation of the transverse mass distribution of the charged lepton-neutrino system from the standard model prediction ...Journal Article -
Measurements of the charm jet cross section and nuclear modification factor in pPb collisions at √sNN = 5.02 TeV
(2017)Physics Letters BThe CMS Collaboration presents the first measurement of the differential cross section of jets from charm quarks produced in proton–lead (pPb) collisions at a nucleon–nucleon center-of-mass energy of √sNN=5.02TeV, as well as results from charm quark jets in proton–proton (pp) collisions at s=2.76 and 5.02TeV. By comparing the yields of the pPb and pp collision systems at the same energy, a nuclear modification factor for charm jets from ...Journal Article -
Search for Low Mass Vector Resonances Decaying to Quark-Antiquark Pairs in Proton-Proton Collisions at √s=13 TeV
(2017)Physical Review LettersA search is reported for a narrow vector resonance decaying to quark-antiquark pairs in proton-proton collisions at √s=13 TeV, collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.7 fb−1. The vector resonance is produced at large transverse momenta, with its decay products merged into a single jet. The resulting signature is a peak over background in the distribution of the invariant ...Journal Article -
Measurements of the associated production of a Z boson and b jets in pp collisions at √s = 8 TeV
(2017)The European Physical Journal CMeasurements of the associated production of a Z boson with at least one jet originating from a b quark in proton–proton collisions at √s=8TeV are presented. Differential cross sections are measured with data collected by the CMS experiment corresponding to an integrated luminosity of 19.8fb−1. Z bosons are reconstructed through their decays to electrons and muons. Cross sections are measured as a function of observables characterizing ...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 -
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