\begin{table}%t9
%\centering
\par
\caption{\label{spc_fits} Median values of the optically thick and
thin spectral indices for the various samples.}
\begin{tabular}{lll}
\hline\hline
Sample     & $\alpha_{\rm thick}$ & $\alpha_{\rm thin}$\\
\hline
HFP    & $-$0.86 & 0.61 \\
Stan   & $-$0.76 & 0.67 \\
B\_SA  & $-$0.38 & 0.76 \\
B\_SB  & $-$0.43 & 0.82 \\
Snel   & $-$0.67 & 0.64  \\
\hline
\end{tabular}
\end{table}