\begin{table}%t1
%\centering
\par
\caption{Geneva photometric measurements of $\alpha$~Cen~A and B.
$P$ corresponds to the weight which varies from
0 to 4 according to the quality of the nights (4 for the best nights and 0 for the worst).}\label{tab:phot}
\begin{tabular}{llll}
\hline
\hline
HJD $-$ 2~430~000 & $V_{\rm A}$ & $V_{\rm B}$ & $P$ \\ \hline
946.718  & $-$    & 1.296 & 1 \\
946.720  & 0.006  & 1.361 & 1 \\
1056.543 & $-$0.023 & 1.357 & 1 \\
1063.558 & 0.003  & 1.331 & 1 \\
1070.518 & 0.006  & 1.344 & 1 \\
1324.808 & 0.001  & $-$   & 1 \\
1688.823 & $-$0.005 & 1.324 & 3 \\ \hline
\end{tabular}
\end{table}