We present a measurement of the $t\overline{t}$ production cross section multiplied by the branching ratio to tau lepton decaying semihadronically (${\tau }_h$) plus jets, $\sigma (p\overline{p}\to t\overline{t}+X)·\mathrm{BR}(t\overline{t}\to {\tau }_h+\mathrm{\text{jets}})$, at a center of mass energy $\sqrt{s}=1.96\mathrm{TeV}$ using $1{\mathrm{fb}}^{-1}$ of integrated luminosity collected with the D0 detector. Assuming a top quark mass of 170 GeV, we measure ${\sigma }_{t\overline{t}}·{\mathrm{BR}}_{{\tau }_h+j}={0.60}_{-0.22}^{+0.23}(\mathrm{stat}{)}_{-0.14}^{+0.15}(\mathrm{syst})\pm 0.04(\mathrm{lumi})\mathrm{pb}$. In addition, we extract the $t\overline{t}$ production cross section using the $t\overline{t}\to {\tau }_h+\mathrm{\text{jets}}$ topology, with the result ${\sigma }_{t\overline{t}}={6.9}_{-1.2}^{+1.2}(\mathrm{stat}{)}_{-0.7}^{+0.8}(\mathrm{syst})\pm 0.4(\mathrm{lumi})\mathrm{pb}$. These findings are in good agreement with standard model predictions and measurements performed using other top quark decay channels.

• Received 25 August 2010

DOI:https://doi.org/10.1103/PhysRevD.82.071102