Search for ttbar resonances in semileptonic final states at 8 TeV with the CMS detector

We present a search for heavy resonances decaying to a top quark-antiquark pair with the Compact Muon Solenoid (CMS) detector in $pp$ collisions at $\sqrt{s} = 8~\text{TeV}$. The analysis is performed in the semileptonic channel and corresponds to the combination of two dedicated searches, one designed for the reconstruction of top decays with well-separated decay products, the other optimized to probe the production of two high-$p_{T}$ top quarks, whose decay can potentially lead to the presence of merged jets and non-isolated leptons at the reconstruction level. No excess is observed in data with respect to the background expectation and $95\%$ CL limits are set on the production cross section of resonances in the mass range from $500~\text{GeV}/c^{2}$ to $3~\text{TeV}/c^{2}$ for several benchmark models.