\begin{table}%t1
\par
\caption{\label{tab1}The peak shifts in the red wing of the H$\alpha$ and
H$\beta$ lines. }
\small%\centerline
{
\begin{tabular}{lccc}
\hline
\hline
H$\alpha$  & $V_{r}$(H$\alpha$) & H$\beta$  &  $V_{r}$(H$\beta$)\\
year\_month &  $ {\rm km~s^{-1}}$      &year\_month &  $ {\rm km~s^{-1}}$     \\
\hline
            &                  &           2001b\_11   &  3257              \\
2002\_1\_3   &     3068         &           2002\_1\_3   &  3257              \\
2002\_4\_5   &     3114         &           2002\_4\_6   &  3196              \\
2002r\_06   &     3068         &                      &                    \\
2002r\_12   &     2977         &           2002b\_12   &  3073              \\
\hline
mean 2002  &     3057 $\pm$ 57     &           mean 2001\_11 + 2002  &  3197 $\pm$ 94          \\
\hline
2003r\_01   &     2886         &           2003b\_01   &  3073              \\
2003r\_05   &     2613         &           2003b\_03   &  3012              \\
2003r\_06   &     2613         &           2003\_5\_6   &  2889              \\
\hline
mean 2003  &     2704 $\pm$ 158    &           mean 2003  &  2991 $\pm$ 94          \\
\hline
2004r\_12   &     2339         &           2004b\_12   &  2273              \\
2005r\_02   &     2294         &           2005\_1\_2   &  2027              \\
2005r\_04   &     2294         &           2005\_5\_6   &  2027              \\
2005r\_06   &     2339         &           2005\_11\_12 &  2338              \\
2006\_1\_2   &     2430         &           2006b\_01   &  2335              \\
           &                  &           2006b\_02   &  2335              \\
2006r\_03   &     2202         &           2006b\_03   &  2150              \\
2006r\_04   &     2294         &           2006b\_04   &  2027              \\
\hline
mean 2004--2006  & 2313 $\pm$ 69     &     mean 2004--2006  & 2189 $\pm$ 147    \\
\hline\\[-3mm] 
\multicolumn{4}{l}{maximal shift $\Delta V_{r}$(H$\alpha$~+~H$\beta )=(1072 \pm 226)~{\rm km~s^{-1}}$} \\
\hline
\end{tabular}}
\smallskip
Columns: 1 -- year and month for H$\alpha$ (e.g.,
2002\_1\_3 = 2002, January and March); 2 -- $V_{r}$(H$\alpha$),
H$\alpha$ peak velocity in the red wing ($ {\rm km~s^{-1}}$); 3 --
year and month for H$\beta$; 4 -- $V_{r}$(H$\beta$), H$\beta$
peak velocity in the red wing (${\rm km~s^{-1}}$). The line after
each year (or interval of years) gives the mean $V_{\rm
r}$(H$\alpha$) and $V_{r}$(H$\beta$) and their standard
deviations. The last line gives the maximal shift of the red peak
($\Delta V_{r}$) from 2002 to 2006. 
\end{table}