Measurements of the top quark pair production cross section in pp collisions at 7 TeV using the CMS detector

Measurements of the top-pair production cross section in proton-proton collisions at the CMS Experiment at the LHC are presented. The data were collected at a centre-of-mass energy of 7 TeV. Measurements performed on an integrated luminosity of 36/pb of data collected in 2010 are presented in top anti-top quark pair final states with one or two leptons (muon or electron) and jets. Moreover, first measurements of the cross section for the production of top quark pairs are presented in the fully hadronic channel, and in the dilepton final state with one muon and one tau-lepton. These measurements make use of 1.1/fb of data recorded in 2011.