Suche
Ergebnisse
-
Measurement of the τ lepton polarization in Z boson decays in proton-proton collisions at √s = 13 TeV
(2024)Journal of High Energy PhysicsJournal Article -
Muon identification using multivariate techniques in the CMS experiment in proton-proton collisions at √s = 13TeV
(2024)Journal of InstrumentationThe identification of prompt and isolated muons, as well as muons from heavy-flavour hadron decays, is an important task. We developed two multivariate techniques to provide highly efficient identification for muons with transverse momentum greater than 10 GeV. One provides a continuous variable as an alternative to a cut-based identification selection and offers a better discrimination power against misidentified muons. The other one ...Journal Article -
Observation of WWγ Production and Search for Hγ Production in Proton-Proton Collisions at √s = 13 TeV
(2024)Physical Review LettersThe observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138 fb⁻¹ is presented. The observed (expected) significance is 5.6 (5.1) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured fiducial cross section for WWγ is WWγ is 5.9 ± ...Journal Article -
Evidence for the Higgs Boson Decay to a Z Boson and a Photon at the LHC
(2024)Physical Review LettersThe first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140fb⁻¹ for each experiment, ...Journal Article -
Search for the lepton flavor violating τ → 3μ decay in proton-proton collisions at √s = 13TeV
(2024)Physics Letters BA search for the lepton flavor violating τ → 3μ decay is performed using proton-proton collision events at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC in 2017–2018, corresponding to an integrated luminosity of 97.7 fb⁻¹. Tau leptons produced in both heavy-flavor hadron and W boson decays are exploited in the analysis. No evidence for the decay is observed. The results of this search are combined with an ...Journal Article -
Universal test system for boards hosting bPOL12V DC-DC converters
(2024)Journal of InstrumentationThe ECAL Barrel and MTD Barrel Timing Layer subdetectors of CMS are approaching series production of electronic boards, including voltage conditioning PCBs: LVRs and PCCs respectively. 2448 LVRs and 864 PCCs will be installed during LS3 of the LHC. These boards are hosting radiation-tolerant bPOL12V ASICs which convert a broad input voltage range into required voltage levels for microelectronics between 1.2-2.5 V. Each card must be tested ...Journal Article -
Measurement of the t¯t production cross section in pp collisions at √s=7 TeV in dilepton final states containing a τ
(2012)Physical Review DThe top quark pair production cross section is measured in dilepton events with one electron or muon, and one hadronically decaying τ lepton from the decay t¯t→(ℓνℓ)(τhντ)b¯b, (ℓ=e,μ). The data sample corresponds to an integrated luminosity of 2.0 fb−1 for the electron channel and 2.2 fb−1 for the muon channel, collected by the CMS detector at the LHC. This is the first measurement of the t¯t cross section explicitly including τ leptons ...Journal Article -
Measurement of the integrated and differential t¯t production cross sections for high-pT top quarks in pp collisions at √s=8 TeV
(2016)Physical Review DThe cross section for pair production of top quarks (t¯t) with high transverse momenta is measured in pp collisions, collected with the CMS detector at the LHC with √s=8 TeV in data corresponding to an integrated luminosity of 19.7 fb−1. The measurement is performed using lepton+jets events, where one top quark decays semileptonically, while the second top quark decays to a hadronic final state. The hadronic decay is reconstructed as a ...Journal Article -
Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at s=13TeV
(2024)Physics Letters BA search is presented for new Higgs bosons in proton-proton (pp) collision events in which a same-sign top quark pair is produced in association with a jet, via the pp→tH/A→ttc‾ and pp→tH/A→ttu‾ processes. Here, H and A represent the extra scalar and pseudoscalar boson, respectively, of the second Higgs doublet in the generalized two-Higgs-doublet model (g2HDM). The search is based on pp collision data collected at a center-of-mass energy ...Journal Article -
Measurements of azimuthal anisotropy of nonprompt D⁰ mesons in PbPb collisions at √sNN = 5.02TeV
(2024)Physics Letters BMeasurements of the elliptic (v₂) and triangular (v₃) azimuthal anisotropy coefficients are presented for Image 1 mesons produced in Image 2 hadron decays (nonprompt Image 1 mesons) in lead-lead collisions at √sNN = 5.02TeV. The results are compared with previously published charm meson anisotropies measured using prompt Image 1 mesons. The data were collected with the CMS detector in 2018 with an integrated luminosity of 0.58nb⁻¹. Azimuthal ...Journal Article