Expectations for observation of top quark pair production in the dilepton final state with the first 10 /pb of CMS data

We present expectations for the observation of top-quark pair production in proton-proton collisions at $\sqrt{s}=14~$TeV with two leptons (electron or muon) in the final state in the early phase of CMS operation. We define a possible event selection and survey the standard model sources of dilepton events. We find that a clear signal stands out in the first $10~\mathrm{pb}^{-1}$\ of CMS data in events selected with two high momentum leptons, missing transverse energy, and at least two jets with expected signal-to-noise ratio of 7 to 1 in all events combined and 25 to 1 in electron-muon final state alone. Based on expected $10~\mathrm{pb}^{-1}$\ of CMS data we expect to measure the top-quark pair production cross section with statistical uncertainty of $9\%$ and a comparable systematic uncertainty.