\begin{table}%t2
\caption{\label{gamma_vel_tab}Parameters of $\gamma^2$ Vel.}
%\begin{center}
{
\begin{tabular}{lcc}
\hline\hline
Parameter & Value & Refs.\\
\hline
$P_{\rm orb}$/days &                     78.5                & 1 \\
$e$               &                    $\sim$0.33           & 1 \\
$\dot{M_{\rm WC}}$/$M_\odot$ yr$^{-1}$ & $2.8\times 10^{-5}$  & 2 \\
$\dot{M_{\rm O}}$ &                      $1.8\times 10^{-7}$  & 3 \\
$V_\infty$(WC) km s$^{-1}$&          1600                & 2 \\
$V_\infty$(O) &                      2500               & 3 \\
$a/R_\odot$  &                        300              & 1 \\
\hline
\end{tabular}}
References:\\
(1) \citet{1997AetA...328..219S}; \\
(2) \citet{1999AetA...345..163D};\\
(3) \citet{2000AetA...358..187D}.
%\end{center}
\par
\end{table}