\begin{table}%t2
\caption {\label{tab-data-sets}
 {\small Overview of the \CI, CO, and $^{13}$CO data of M~83 and M~51. 
$\theta_{\rm b}$ is the telescope half power beamwidth.
All spectra are scaled to main beam brightness temperatures, 
$T_{\rm mb}=T_{\rm A}^*/\eta_{\rm{mb}}$. }}
%
%% 5: \citet{regan2001};       % M~51 CO 1-0 data not needed anymore
%% 3: \citet{israel_baas2002};
%% 5: Lord et al. (priv. com.);
%\centerline
{\begin{tabular}{rrrrrcl}
\hline \hline
% Positions 
& Line & $\theta_{\rm{b}}$ & Telescope & $\eta_{\rm{mb}}$ & Refs. \\
% ($\Delta\alpha,\Delta\delta$) 
&      & ($''$) \\
% ($'',''$) &      &  \\
\hline
\multicolumn{7}{l}{{\bf M~83} at (0, 0), (89, 38), ($-80, -72$)} \\ 
            & \CI\ 1--0 & 10 & JCMT 15~m & 0.52 & 1 & point. \\
            & CO 1--0   & 21 & IRAM 30~m & 0.78 & 1 & point. \\
            & CO 1--0   & 55 & NRAO 12~m & 0.88 & 2 & map \\ % Crosthwaite et al.
%%(0,0)     & CO 2--1   & 21 & JCMT 15m & 0.63 & 3 \\ % is replaced by IRAM 30m data
            & CO 2--1   & 10 & IRAM 30~m & 0.57 & 1 & point. \\
            & CO 2--1   & 28 & NRAO 12~m & 0.56 & 2 & map \\ % Crosthwaite et al.
%%%
%%center                  & CO 3--2   & 14 & JCMT 15m & 0.53 & 3 \\ % new.
            & CO 3--2   & 25 & CSO 10~m  & 0.75 & 3 & map \\ %new: also at center: use it !!
%%center    & CO 4--3   & 11 & JCMT 15m & 0.51 & 3 \\ % new.
%%%
            & $^{13}$CO 1--0 & 22 & IRAM 30~m & 0.79 & 1 & point. \\
%%(0,0)     & $^{13}$CO 2--1 & 21 & JCMT 15m & 0.63 & 3 \\ % This JCMT spectrum looks strange compared 
%%                                                           to those of 13CO 1-0 and 3-2 ! -- leave out.
            & $^{13}$CO 2--1 & 10 & IRAM 30~m & 0.60 & 1 & point. \\ % new: also at center = observe !!.
%%center    & $^{13}$CO 3--2 & 14 & JCMT 15m & 0.62 & 3 \\ %new: not used in this paper!
%%%
%% (0,0),(89,38),($-80,-72$) & [CII]     & 70 & ISO      & 1.0  & 5 \\
\hline %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\multicolumn{7}{l}{{\bf M~51} at (0, 0), (72, 84), ($-84,-84$)} \\
% , ($-30,48$), and ($-5,62$)} \\
                          & \CI\ 1--0 & 10 & JCMT 15~m & 0.52 & 1 & point \\ 
                                              % 0.52 taken from wwww; Israel & Baas 2002: eta_mb=0.50, 10.2''
%                          & CO 1--0   & 21 & IRAM 30m & 0.78 & 1 & point. \\ % (cf 7) \\
                          & CO 1--0   & 21 & IRAM 30~m & 0.65 & 5 & map \\ % Garcia-Burillo et al. 1993
%                          & CO 1--0   &  5 & BIMA/NRAO & xxx & 5 & map \\ % Regan et al. BIMA/SONG
%
%                          & CO 2--1   & 10 & IRAM 30m & 0.57 & 1 & point. \\ 
                          & CO 2--1   & 10 & IRAM 30~m & 0.46 & 5 & map \\ 
%
                          & CO 3--2   & 22 & HHT 10~m  & 0.50 & 4 & map \\ % Wielebinski et al. 1999
%                          & CO 4--3   & 17 & HHT 10m  & 0.50 & 4 & map \\ % Nieten et al. 1999
                          & $^{13}$CO 1--0 
                                      & 22 & IRAM 30~m & 0.79 & 1 & point. \\ % (cf 7) \\
                          & $^{13}$CO 2--1 
                                      & 10 & IRAM 30~m & 0.60 & 1 & point. \\ % (cf 7) \\
\hline
\end{tabular}}
\smallskip
References: 
1: new data for this paper; 
2: \citet{crosthwaite2002};
3: Bayet et al. (priv. comm.);
4: \citet{wielebinski1999}, \cite{nieten1999}, \cite{dumke2001};
5: \citet{gb1993a}. 
The last column indicates whether single pointings or maps are available.
The mapped CO~data was Gauss-smoothed to the $80''$ ISO/LWS \mbox{resolution}.
\end{table}