Search for \( \mathrm{t}\overline{\mathrm{t}} \) resonances in highly boosted lepton+jets and fully hadronic final states in proton-proton collisions at \( \sqrt{s}=13 \) TeV
A search for the production of heavy resonances decaying into top quark-antiquark pairs is presented. The analysis is performed in the lepton+jets and fully hadronic channels using data collected in proton-proton collisions at \( \sqrt{s}=13 \) TeV using the CMS detector at the LHC, corresponding to an integrated luminosity of 2.6 fb−1. The selection is optimized for massive resonances, where the top quarks have large Lorentz boosts. No evidence for resonant \( \mathrm{t}\overline{\mathrm{t}} \) production is found in the data, and upper limits on the production cross section of heavy resonances are set. The exclusion limits for resonances with masses above 2 TeV are significantly improved compared to those of previous analyses at \( \sqrt{s}=8 \) TeV.
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