Measurement of Top Quark Pair Differential Cross Sections at sqrt(s) = 7 TeV

Normalized differential top quark pair production cross sections are measured in pp~collisions at $\sqrt{s} = 7\TeV$ with the CMS detector using a dataset recorded in 2011 corresponding to an integrated luminosity of 1.14 $\pm$ 0.05\fbinv. The measurement is performed in the semileptonic decay channels (\ejets and \mujets) and the dileptonic decay channels (\mumu, \ee and \mue). The top quark kinematic properties are obtained by use of kinematic fitting algorithms. The cross sections are measured as a function of the transverse momentum, (pseudo-)rapidity, and invariant mass of the final state leptons, the top quarks, and the \ttbar system. Good agreement is found with predictions from different QCD models.