\begin{table}%t1
\caption{\label{tab:vespa_tab}Parameters of the IRAM 30~m observations.}
%\centerline
{
\begin{tabular}{lcccc} 
\hline
\hline
 {Line} & {Frequency} & {Resolution} & {Bandwidth} & {Mean rms} \\
  &   &  & & {noise$^a$}\\ 
  & {(GHz)} & {(km~s$^{-1}$)} & {(km~s$^{-1}$)} & {(K)} \\ 
\hline  
 {$^{12}$CO(2--1)} & {230.5379} & {0.84} & {157} & 0.1 \\
 {$^{13}$CO(2--1)} & {220.3986} & {0.10} & {78} & 0.2 \\ 
 {C$^{18}$O(2--1)}& {219.5603} & {0.10} & {78} & 0.3 \\ 
 \hline 
\end{tabular}}
\medskip
$^a$ {rms noise per spectral resolution element.}
\end{table}