Measuring the differential cross section for top quark production at 8TeV

Abstract

Normalized differential top quark pair production cross sections are measured in pp collisions at a centre-of-mass energy of 8 TeV at the LHC using the CMS detector. The dataset used for these measurements corresponds to an integrated luminosity of 19.7 fb −1 . The measurements are performed in the lepton+jets (e+jets and µ+jets) and in the dilepton (ee, µ µ, and eµ) decay channels. The tt production cross section is measured as a function of kinematic properties of the charged leptons, the jets associated to b-quarks, the top-quarks, and the tt system. The data are compared with several predictions from perturbative QCD calculations up to approximate nextto-next-to-leading-order precision. No significant deviations with respect to the standard model predictions are observed.