\begin{table}%t3
\caption{\label{ice_detect}Detection of ice features in our YSO spectra.}
%\centering
\par
\begin{tabular}{ c c c c c c c }
\hline\hline \noalign{\smallskip}
Number  &   H$_2$O  &  CO$_2$   &    CO     &  CH$_3$OH & $^{13}$CO$_2$ & XCN \\
\hline \noalign{\smallskip}
ST1     &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &    ---    &    ---  \\
ST2     &  $\surd$  &  $\surd$  &    ---    &  $\surd$  &     ?     &    ---  \\
ST3     &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &    ---    &    ---  \\
ST4     &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &    ---    &    ---  \\
ST5     &  $\surd$  &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &    ---  \\
ST6     &    ---    &  $\surd$  &  $\surd$  &    ---    &    ---    &     ?   \\
ST7     &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &  $\surd$  &     ?   \\
ST8     &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &  $\surd$  &    ---  \\
ST9     &     ?     &  $\surd$  &  $\surd$  &    ---    &     ?     &    ---  \\
ST10    &  $\surd$  &  $\surd$  &  $\surd$  &    ---    &    ---    &     ?   \\
ST11    &  $\surd$  &  $\surd$  &    ---    &     ?     &    ---    &    ---  \\
ST12    &  $\surd$  &  $\surd$  &    ---    &     ?     &    ---    &    ---  \\[2pt]
\hline 
\end{tabular}
\tablefoot {$\surd$ = clear detection, ? = tentative detection, --- = no detection.}\vspace{-3mm}
\end{table}