Measurement of the top quark pair production cross section in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mtext mathvariant="normal">lepton</mml:mtext><mml:mo>+</mml:mo><mml:mtext mathvariant="normal">jets</mml:mtext></mml:math>channel in proton-antiproton collisions at<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msqrt><mml:mi>s</mml:mi></mml:msqrt><mml:mo>=</mml:mo><mml:mn>1.96</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math>

Abstract

We present a measurement of the inclusive top quark pair production cross\nsection in \\ppbar collisions at (\\sqrt{s}=1.96) TeV utilizing data\ncorresponding to an integrated luminosity of \\lumi\\ collected with the D0\ndetector at the Fermilab Tevatron Collider. We consider final states containing\none high-$p_{T}$ isolated electron or muon and at least two jets, and we\nperform three analyses: one exploiting specific kinematic features of \\ttbar\nevents, the second using $b$-jet identification, and the third using both\ntechniques to separate \\ttbar\\ signal from background. In the third case, we\ndetermine simultaneously the $t\\bar{t}$ cross section and the ratio of the\nproduction rates of $W$+heavy flavor jets and $W$+light flavor jets, which\nreduces the impact of the systematic uncertainties related to the background\nestimation. Assuming a top quark mass of 172.5 GeV, we obtain\n$\\sigma_{t\\bar{t}} = 7.78^{+0.77}_{-0.64} $ pb. This result agrees with\npredictions of the standard model.\n