We present a new measurement of $p\bar p \to t \bar tX$ production
at $\sqrt{s}=1.96$ TeV using 4951.86 pb$^{-1}$ of data collected with the
D0 detector between 2002 and 2010. We focus on the final state
where the $W$ boson from one of the top quarks decays into a
$\tau$ lepton and its associated neutrino, while the other $W$ boson decays into
a quark-antiquark pair. We aim to select those events in which the
$\tau$ lepton subsequently decays hadronically, meaning to one or more charged hadrons, zero
or more neutral hadrons and a tau neutrino. We train a topological neural network
as the method to enhance signal over the background. For a top quark
mass of 172.5 GeV we measure the cross section to be:
\begin{center}\[\sigma (t\overline{t}) =
8.46\;\;_{-1.04}^{+1.06}\;\;({\textrm{stat}})\;\;_{-0.78}^{+0.84}\;\;({\textrm{syst}})\;\;\pm 0.3\;\;({\textrm{lumi}})\;\; \rm{pb.}\]
\par\end{center}
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