Measurement of the cross section for tt̄ production in pp̄ collisions using the kinematics of lepton+jets events

We present a measurement of the top pair production cross section in p (p) over bar collisions at root s=1.96 TeV. We collect a data sample with an integrated luminosity of 194 +/- 11 pb(-1) with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton+jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be sigma(t (t) over bar)=6.6 +/- 1.1 +/- 1.5 pb, where the first uncertainty is statistical and the second is systematic.