Search for the production of W$^\pm$W$^\pm$W$^\mp$ events at $\sqrt{s} =$ 13 TeV
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Abstract (data abstract)
CERN-LHC. A search for the production of events containing three W bosons predicted by the standard model is reported. The search is based on a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the CERN LHC and corresponding to a total integrated luminosity of 35.9 $\mathrm{fb}^{−1}$. The search is performed in final states with three leptons (electrons or muons), or with two same-charge leptons plus two jets. The observed (expected) significance of the signal for $\mathrm{W}^{\pm}\mathrm{W}^{\pm}\mathrm{W}^{\mp}$ production is 0.60 (1.78) standard deviations, and the ratio of the measured signal yield to that expected from the standard model is \$0.34^{+0.62}_{−0.34}. Limits are placed on three anomalous quartic gauge couplings and on the production of massive axion-like particles. The two equally charged (SS) channel fiducial region is defined as - exactly 2e, 2mu or 1e1mu with both leptons having the same charge - ptLepton > 25 GeV - |etaLepton| < 2.4 - the invariant mass of the two leptons has to be >40 (30) GeV for 2e or 2mu (emu) and |mll - mZ| > 10 GeV for 2e - at least two jets, none of them b tagged - ptJet > 30 GeV - |etaJet| < 2.5 - The invariant mass of the two highest pt jets has to be mJJ < 400 GeV - The DeltaEta of the two highest pt jets has to be <1.5 - The missing transverse momentum has to be > 60 GeV, except for the 2mu region if the invariant mass of the two jets closest in DeltaR is between 65 and 90 GeV - The maximum of the transverse masses constructed out of the momenta of a charged lepton and the missing transverse momentum has to be >90 GeV for 1e1mu. - For the interpretation in anomalous quartic gauge couplings, the selection on the invariant mass of the two highest pt jets is not applied, but we select ST > 2 TeV, where ST is the scalar sum of the transverse momenta of all leptons, jets, and the missing transverse momentum The three charged lepton (3l) channel fiducial region is defined as - 3e, 2e1mu, 1e2mu or 3mu with the sum of the three lepton charges being 1 or -1 - ptLepton > 20 GeV, but one lepton has to have > 25 GeV - |etaLepton| < 2.4 - the transverse momentum of the three-lepton system has to be >60 GeV except if there is no same-flavor differently-charged (SFOS) lepton pair in the event - the invariant mass of the three-lepton system has to be |mlll - mZ| > 10 GeV - the invariant mass of any SFOS lepton pair has to be > 20 GeV and |mSFOS - mZ| > 20 GeV - the invariant mass of two electrons has to be |mee - mZ| > 15 GeV if no SFOS lepton pair is found - the invariant mass of two charged leptons with same flavor has to be > 20 GeV if no SFOS lepton pair is found - the angular separation in the transverse plane between the three-lepton system and the missing transverse momentum has to be > 2.5 - The maximum of the transverse masses constructed out of the momenta of a charged lepton and the missing transverse momentum has to be >90 GeV if no SFOS lepton pair is found. - The the transverse masses constructed out of the momenta of charged lepton, which is not part of any SFOS lepton pair, and the missing transverse momentum has to be >90 GeV if one SFOS lepton pair is found. - the missing transverse momentum has to be > 30 GeV if no SFOS lepton pair is found, > 45 GeV if 1 SFOS lepton pair is found, and > 55 GeV if 2 SFOS lepton pairs are found - at most one jets, none of them b tagged - ptJet > 30 GeV - |etaJet| < 5.0 - For the interpretation in anomalous quartic gauge couplings, we select ST > 1.5 TeV, where ST is the scalar sum of the transverse momenta of all leptons, jets, and the missing transverse momentum