\begin{table}%t2
%\centering
\par
\caption{\label{table:prewhite}Frequencies and amplitudes of the radial velocity measurements found by the pre-whitening procedure.}
\begin{tabular}{cccc}
\hline\hline
Frequency   &  Period & Amplitude &   Phase   \\
(c~d$^{-1}$)   &d     &       (m~s$^{-1}$) &  \\
\hline
0.0432 &23.15 &7.50 &  0.87   \\
0.1108  & 9.03&6.20 &  0.83    \\
0.0944  & 10.6&5.69 &  0.05    \\
0.2706  & 3.69&5.02 &  0.22    \\
1.1702  & 0.854&4.36 &  0.16  \\
0.0363  & 27.6&5.68 &  0.38    \\
0.1814  & 5.5&3.10 &  0.61      \\
0.0716  & 14.00&3.26 &  0.64   \\
0.2516  & 3.975&1.78 &  0.38   \\
0.1373  & 7.28&1.85 &  0.88     \\
0.1649  & 6.06&1.97 &  0.53     \\
0.0228  & 43.8&2.14 &  0.75     \\
\hline
$\sigma$ = 1.81 m~s$^{-1}$ & \\
\hline
\end{tabular}
\end{table}