CMS-PAS-TOP-17-019 | ||
Search for standard model production of four top quarks with the single-lepton and opposite-sign dilepton final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV | ||
CMS Collaboration | ||
March 2019 | ||
Abstract: A search for the standard model production of four top quarks ($\mathrm{pp \rightarrow t\bar{t}t\bar{t}}$) is reported using events with single-lepton ($\mathrm{e}$, $\mu$) + jets and opposite-sign dilepton ($\mu^+\mu^-$, $\mu^\pm \mathrm{e}^\mp$, or $\mathrm{e^+e^-}$) + jets signatures. The events are collected in proton-proton collisions recorded by the CMS detector at the LHC at $\sqrt{s}= $ 13 TeV in a sample corresponding to an integrated luminosity of 35.8 fb$^{-1}$. A multivariate analysis using global event and jet properties based on boosted decision trees is used to discriminate $\mathrm{t\bar{t}t\bar{t}}$ from $\mathrm{t\bar{t}}$ production. No significant deviation is observed from the predicted background. An upper limit is set on the cross section for $\mathrm{t\bar{t}t\bar{t}}$ production in the standard model of 48 fb at 95$%$ confidence level. When combined with the previous measurement of $\sigma_\mathrm{t\bar{t}t\bar{t}}$ by the CMS experiment from an analysis of other final states, the observed signal significance is 1.4 standard deviations and the combined cross section measurement is $\sigma_\mathrm{t\bar{t}t\bar{t}} = $ 13$^{+11}_{-9}$ fb. | ||
Links:
CDS record (PDF) ;
inSPIRE record ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, JHEP 11 (2019) 082. The superseded preliminary plots can be found here. |
Compact Muon Solenoid LHC, CERN |