\begin{table}%t3
\caption{\label{tab3}The beginning and end radial velocities, $V_{\rm beg}$
and $V_{\rm end}$, in km~s$^{-1}$ for different segments of the line
profiles.} 
\small%\centering
$$
\begin{tabular}{llllllllllll}
\hline
\hline
\backslashbox[0pt][l]{$V_{r}$}{Segment} & --5    &   --4  &  --3   &  --2   &  --1  &  0(C) & +1  &   +2  &   +3  &  +4  &  +5   \\
\hline
$V_{\rm beg}$   &  --5500  & --4500 & --3500 & --2500 & --1500 & --500 &  500 & 1500 &  2500 &  3500 & 4500   \\
$V_{\rm end}$   &  --4500  & --3500 & --2500 & --1500 &  --500 &  500 & 1500 & 2500 &  3500 &  4500 & 5500    \\
\hline
\end{tabular}$$
\end{table}