\begin{table}%t5 \caption{\label{n4441chap_13cotab}Parameters of $\rm ^{12}$CO and $\rm ^{13}$CO at the central position.} \small%\centerline { \begin{tabular}{lccccccccc} \hline\hline \noalign{\smallskip} Line & \multicolumn{2}{c}{Central velocity (lsr)} & \multicolumn{2}{c}{Linewidth} & \multicolumn{2}{c}{Peak} & int. Intensity \\ & \multicolumn{2}{c}{(km~s$^{-1}$)} & \multicolumn{2}{c}{(km~s$^{-1}$)} & \multicolumn{2}{c}{(K)} & (K~km~s$^{-1}$)\\ \hline $\rm ^{12}$CO(1--0)& 2698 & 2796 &125 & 147 & 0.02 & 0.036& 7.52 $\pm$ 0.22\\ $\rm ^{12}$CO(2--1)& 2655 & 2802&93 & 114& 0.016, & 0.039& 6.10 $\pm$ 0.73\\ $\rm ^{13}$CO(1--0)& \multicolumn{2}{c}{2725}& \multicolumn{2}{c}{208} & \multicolumn{2}{c}{0.0018}& 0.37 $\pm$ 0.06\\ $\rm ^{13}$CO(2--1)& \multicolumn{2}{c}{2785}&\multicolumn{2}{c}{61}& \multicolumn{2}{c}{0.0033} & 0.25 $\pm$ 0.09\\ \hline \end{tabular}} \medskip Gaussians were fitted to determine linewidths, peak intensity, and central velocity. For~$\rm ^{12}$CO, we fitted two components to the measured line, whereas for $\rm ^{13}$CO only one component was fitted. The given intensity is integrated over both components. Temperatures are given in~$T_{\rm MB}$. \end{table}