\begin{table}%ta
\par
\caption{\label{tdts}Log of the observations used.}
%\centerline
 {
\begin{tabular}[!t]{lcccc}
\hline
\hline
Transition & Observing  & ISO TDT      & LWS        & Resolution \\
           & Mode       & Number       & Detector   & (km~s$^{-1}$) \\
\hline 
\multicolumn{5}{l}{{\bf $^{{\bf 12}}$CH and $^{{\bf 13}}$CH  \object{Sgr~B2} } } \\
$J=3$/2--1/2  (149~$\mu$m)   & L03  & 50700208 & LW3 & 36    \\
 (\& para-CH$_{2}$ 3$_{12}$--3$_{03}$$^{a}$) & L03  & 84500102 & LW3 & 36    \\
                             & L03  & 50600603 & LW3 & 36    \\
                             & L03  & 50600814 & LW4 & 36    \\
                             & L03  & 50900521 & LW4 & 36    \\
$J=3$/2--5/2  (115~$\mu$m)$^{a}$  & L03  & 50601013 & LW2 & 34    \\
\hline 
\multicolumn{5}{l}{{\bf ortho-CH$_{{\bf 2}}$ \object{Sgr~B2}}}   \\
1$_{11}$--0$_{00}$ (127~$\mu$m) & L03  & 50700511 & LW2 & 34    \\
                                & L03  & 50800819 & LW3 & 34    \\
                                & L04  & 47600907 & LW2 & 34    \\
2$_{11}$--2$_{02}$ (153~$\mu$m)$^{a}$ & L03  & 50700208 & LW4 & 35    \\
                                      & L03  & 50800317 & LW4 & 35    \\
                                      & L03  & 50400823 & LW4 & 35    \\
                                      & L03  & 50600405 & LW3 & 35    \\
                                      & L03  & 83600317 & LW3 & 35    \\
3$_{13}$--2$_{02}$ (94~$\mu$m)  & L03  & 50800218 & LW1 & 34    \\
                                & L03  & 50400823 & LW1 & 34    \\
                                & L03  & 50700610 & LW1 & 34    \\
2$_{20}$--1$_{11}$ (50~$\mu$m)$^{a}$ & L03  & 50800218 & SW2 & 64    \\
\hline 
\multicolumn{5}{l}{{\bf para-CH$_{{\bf 2}}$ \object{Sgr~B2}}}   \\
1$_{10}$--1$_{01}$ (156~$\mu$m)$^{b}$  & L03  & 50700707 & LW4 & 35    \\
                                       & L03  & 50700610 & LW4 & 35    \\
                                       & L03  & 50800317 & LW4 & 35    \\
2$_{12}$--1$_{01}$ (107~$\mu$m) & L03  & 50800515 & LW2 & 32    \\
                                & L03  & 50800819 & LW2 & 32    \\
2$_{21}$--1$_{10}$ (51~$\mu$m)$^{a}$ & L03  & 50800216 & SW2 & 64    \\
                                     & L03  & 50600814 & SW2 & 64    \\
                                     & L03  & 50700511 & SW2 & 64    \\
                                     & L03  & 50900521 & SW2 & 64    \\
\hline 
\hline 
\multicolumn{5}{l}{{\bf CH$_{{\bf 2}}$ \object{W49~N}}} \\
1$_{11}$--0$_{00}$ (127~$\mu$m)       & L04  & 49900406 & LW2 & 34    \\
2$_{12}$--1$_{01}$ (107~$\mu$m)$^{a}$ & L04  & 49900406 & LW2 & 32    \\
\hline 
\multicolumn{5}{l}{{\bf CH \object{W49~N}}}   \\
$J=3$/2--1/2  (149~$\mu$m)            & L01  & 52700702 & LW4 & 1200   \\
\hline 
\hline 
\multicolumn{5}{l}{{\bf CH$_{{\bf 2}}$ \object{Sgr~A$^{{\bf \ast}}$}}}  \\
1$_{11}$--0$_{00}$ (127~$\mu$m)$^{a}$ & L03  & 50900204 & LW2 & 34    \\
2$_{12}$--1$_{01}$ (107~$\mu$m)$^{a}$ & L03  & 50800902 & LW2 & 32    \\
                                      & L03  & 85000139 & LW2 & 32    \\
                                      & L03  & 50900444 & LW1 & 32    \\
                                      & L03  & 85000247 & LW1 & 32    \\
\hline 
\multicolumn{5}{l}{{\bf CH \object{Sgr~A$^{{\bf \ast}}$}}}   \\
 $J=3$/2--1/2  (149~$\mu$m)           & L03  & 84900448 & LW3 & 34    \\
\hline
\hline
\multicolumn{5}{l}{{\bf CH$_{{\bf 2}}$ \object{NGC~7023}} (3 different positions)}   \\
1$_{11}$--0$_{00}$ (127~$\mu$m)$^{a}$ & L04  & 33901603 & LW2 & 34    \\
                                      & L04  & 34601501 & LW2 & 34    \\
                                      & L04  & 56000208 & LW2 & 34    \\
\hline
\end{tabular}
}
\par
$^{a}$ Not detected.\\
$^{b}$ Blended with NH line.
\end{table}