\begin{table}%t4
\caption{\label{table:ls_periods}The spin periods (in seconds) obtained from Lomb-Scargle periodograms, using data from \xmm\ and \rxte.}
%\centering
\small
\begin{tabular}{lcc}
\hline\hline
Observation &     $0.2{-}10$ keV        &  $5{-}30$ keV       \\
\hline  
1           &     $62.19\pm0.02$     &       --         \\
2           &     $61.28\pm0.02$     &  $61.23\pm0.06$  \\
3           &     $60.65\pm0.01$     &  $60.62\pm0.3$  \\
4           &     $60.64\pm0.01$     &      --          \\
\hline
\end{tabular}
\end{table}