\begin{table}%t4
   \caption{Differential radial velocities of HD~219542~A.}
     \label{t:hd219542a}
%\centering
\par
       \begin{tabular}{ccc}
         \hline
         \hline
         JD--2~450~000  &  $RV$ & error  \\
         \hline
       1825.52  &      $-$7.2  &     5.8  \\
       1826.59  &      $-$6.0  &     8.6  \\
       2070.70  &      $-$1.9  &     3.8  \\
       2071.70  &       1.9  &     3.9  \\
       2072.68  &       1.0  &     4.5  \\
       2113.69  &      $-$2.4  &     4.1  \\
       2115.67  &      $-$3.8  &     4.5  \\
       2115.71  &       4.0  &     5.1  \\
       2116.56  &       5.8  &     8.2  \\
       2116.70  &      $-$1.4  &     5.6  \\ 
       2117.68  &       5.2  &     3.9  \\
       2120.71  &       1.1  &     5.0  \\
       2145.65  &      $-$1.4  &     4.0  \\
       2190.53  &       4.0  &     4.5  \\
       2216.46  &      $-$5.5  &     7.7  \\
       2245.42  &      $-$3.1  &     4.4  \\ 
       2424.70  &       3.7  &     4.6  \\
       2445.70  &      11.6  &     4.5  \\
       2472.70  &       7.9  &     6.0  \\
       2504.67  &      $-$7.2  &    11.0  \\
       2538.50  &      $-$7.5  &     5.9  \\
       2570.40  &      $-$2.1  &     4.9  \\
       2585.46  &      12.9  &     7.3  \\
       2597.36  &      $-$2.3  &     5.2  \\
       2605.35  &      $-$7.3  &     5.1  \\
         \hline
      \end{tabular}
\end{table}