First look at top-quark selections with 13 TeV data

This Performance Note presents some illustrative event displays and distributions of observables designed to study top-quark pairs, in the electron plus muon and in the single-lepton plus jets final states, and an event that passes a selection designed for single top produced by the t-channel electroweak mechanism with a single-muon final state. The data set consists of the first proton-proton collision data recorded by the CMS detector at a center-of-mass energy of 13 TeV with a magnetic field of 3.8 Tesla in the solenoid, during the LHC development run with a bunch spacing of 50 ns that took place in July 2015. Uncorrected Monte Carlo expectations are compared to data. For the simulation of top-quark pair events, the POWHEG generator is used for the hard partonic process, interfaced with Pythia8 for parton showering and hadronization.