Evidence for associated production of a single top quark and W boson in pp collisions at sqrt(s) = 7 TeV

Abstract

Evidence is presented for the associated production of a single top quark and W boson in pp collisions at sqrt(s) = 7 TeV with the CMS experiment at the LHC. The analyzed data corresponds to an integrated luminosity of 4.9 inverse femtobarns. The measurement is performed using events with two leptons and a jet originated from a b quark. A multivariate analysis based on kinematic properties is utilized to separate the t t-bar background from the signal. The observed signal has a significance of 4.0 sigma and corresponds to a cross section of 16 +5 -4 pb, in agreement with the standard model expectation of 15.6 +/-0.4 +1.0 -1.2 pb.

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