\begin{table}%t7
\caption{Excitation temperatures ($T_{\rm ex}$), optical depths, source-averaged 
column and number
densities derived from the $^{12}$CO and~$^{13}$CO line data. The column and number
densities are of H$_{2}$ and are calculated assuming a $^{12}$CO/$^{13}$CO ratio of 60
and a $^{12}$CO/H$_{2}$ abundance ratio of 10$^{-4}$.}
\label{tbl:linedata}
%\centering
\par
\begin{tabular}{lccccc}
\hline
\hline
Source ID &  $T_{\rm ex}$ & \multicolumn{2}{c}{Optical depth} & $\log(N)$ &
$\log(n)$ \\
 & (K) & $^{12}$CO & $^{13}$CO & (cm$^{-2}$) & (cm$^{-3}$) \\ 
 \hline
 \object{SFO 11 SMM1} &  22 & 26.4 & 0.4 & 21.4 & 3.4 \\
 \object{SFO 11 SMM2} &  19 & 24.1 & 0.4 & 21.3 & 3.5 \\
 \object{SFO 11 SMM3} &  14 & 25.1 & 0.4 & 21.1 & 3.4 \\
 & & & & &  \\ 
 \object{SFO 11NE SMM1} & 14 & 48.2 & 0.8 & 21.5 & 3.6 \\
 \object{SFO 11NE SMM2} & 15 & 28.5 & 0.5 & 21.4 & 3.7 \\
& & & & & \\
 \object{SFO 11E SMM1} & 15 & 39.4 & 0.7 & 21.4 & 3.5 \\
 \object{SFO 11E SMM2} & 23 & 23.2 & 0.4 & 21.5 & 3.9 \\
 \object{ \object{SFO 11E SMM3}} & 17 & 31.1 & 0.5 & 21.5 & 3.9 \\ \hline
\end{tabular}
\end{table}