Measurement of tt̄ production in the τ+jets topology using pp̄ collisions at √s=1.96TeV

We present a measurement of the tt̄ production cross section multiplied by the branching ratio to tau lepton decaying semihadronically (τh) plus jets, σ(pp̄→tt̄+X) •BR(tt̄→τh+jets), at a center of mass energy √s=1.96TeV using 1fb⊃-1 of integrated luminosity collected with the D0 detector. Assuming a top quark mass of 170 GeV, we measure σ tt̄•BRτh+j=0.60-0.22+0.23(stat)- 0.14+0.15(syst)±0.04(lumi)pb. In addition, we extract the tt̄ production cross section using the tt̄→τh+jets topology, with the result σtt̄=6.9-1.2+1.2(stat)-0.7+0. 8(syst)±0.4(lumi)pb. These findings are in good agreement with standard model predictions and measurements performed using other top quark decay channels. © 2010 The American Physical Society.