Measurement of the tt¯ production cross section in the dilepton channel in pp collisions at √s=7 TeV

Abstract

The tt¯ production cross section (σtt¯) is measured in proton-proton collisions at s√=7 TeV in data collected by the CMS experiment, corresponding to an integrated luminosity of 2.3 fb−1. The measurement is performed in events with two leptons (electrons or muons) in the final state, at least two jets identified as jets originating from b quarks, and the presence of an imbalance in transverse momentum. The measured value of σtt¯ for a top-quark mass of 172.5 GeV is 161.9±2.5(stat.)+5.1−5.0(syst.)±3.6(lumi.)pb, consistent with the prediction of the standard model.