\begin{table}%T6
\caption{General \hi~properties of companion galaxies.}
\label{tab:compprops}
%\centerline
{
\begin{tabular}{lccccc}
\hline\hline
  & NGC~1511a & NGC~1511b & NGC~4562 & NGP9~F378-0021557 & 2MASX~J12485413-1140424 \\
\hline
$\alpha$(2000)  & 04:00:17.9 & 04:00:53.2 & 12:35:34.8 & 12:36:20.2 
  & 12:48:54.2 \\
$\delta$(2000)  & --67:48:26 & --67:36:38 & +25:51:09 & +26:04:59 
  & --11:40:32 \\
$D$ (Mpc)$^a$  & 17.5 & 17.5 & 9.7 & 9.7 & 25.5 \\
$v_{\rm hel}$ (km s$^{-1}$) & 1339$\;\pm\;$5 & 1420$\;\pm\;$10 & 1347 & 1260$\;\pm\;$5 
  & 1329$\;\pm\;$5 \\
$v_{\rm max}$ (km s$^{-1}$) & 55$\;\pm\;$10 & 27 & 33 & -- & -- \\
{\it i} ($^\circ$) & -- & 81 & 86 & -- & -- \\
{PA} ($^\circ$) & 268 & 85 & 121 & -- & 0$\;\pm\;$5\\
$f_{\rm HI}$  (Jy~km~s$^{-1}$) & 2.91 & 4.79 & 5.34 & 0.91 & 3.10 \\
$M_{\rm atom}$  ($10^{9}$ \msol) & 0.28 & 0.47 & 0.16 & 0.027 & 0.64 \\
\hline
\end{tabular}}
\par
\medskip
Notes: \\
$^{a}$ Distances are based on $H_0$~= 75 Mpc~km~s$^{-1}$ and a
virgocentric infall velocity of 300~km~s$^{-1}$ (cf. Dahlem et
al. \cite{Dahlem01}). They are assumed here to be the same as those of the
dominant galaxies in the respective groups (Table~\protect\ref{tab:hiprops}).
%\vspace*{1.5mm}
\end{table}