  We discuss cross sections for $\nu_{\tau}$ and ${\overline \nu}_{\tau}$
production from the direct $D_s^{\pm} \to \nu_{\tau}/{\overline \nu}_{\tau}$
and chain $D_s^{\pm} \to \tau^+/\tau^- \to \nu_{\tau}/{\overline \nu}_{\tau}$
decays in $p\!+^{96}\!\mathrm{Mo}$ scattering with proton beam
$E_{\mathrm{lab}}$ = 400 GeV \textit{i.e.} at $\sqrt{s}_{NN}$ = 27.4 GeV. In
our calculations we include $D_s^{\pm}$ from charm fragmentation $c \to
D_s^{+}$ and $\bar c \to D_s^-$ as well as those from subleading fragmentation
of strange quarks/antiquarks $s \to D_s^-$ and $\bar s \to D_s^+$. The
different contributions to $D_s^{\pm}$ and $\nu_{\tau} / {\overline
\nu}_{\tau}$ production rates are shown explicitly. Estimates of a number of
observed $\nu_{\tau} / \overline{\nu}_{\tau}$ in the $\nu_{\tau} /
\overline{\nu}_{\tau} +^{208}\!\mathrm{Pb}$ reaction, with 2m long target are
given.
