Measurement of the $\mathrm{t\bar t}$ production cross section in the dilepton channel in proton-proton collisions at $\sqrt{s}$~=~8 TeV with the CMS experiment

The cross section for top quark pair production is measured in proton-proton collisions at $\sqrt{s}=$~8~TeV in a data sample corresponding to 2.4 fb$^{-1}$ of integrated luminosity collected by the CMS experiment in 2012. The measurement is performed with events with two leptons (electrons or muons), as well as with identified b-quark jets in the final state. The combined measured cross section is $\sigma_{t\bar t}=~$227~$\pm$~3~(stat.)~$\pm$~11~(syst.)~$\pm$~10~(lumi.)~pb, in agreement with theoretical predictions.