\begin{table}%t1
\caption{\label{table:obs}Specifications for the different sub-samples.}
\par
%\centering
\par
\begin{tabular}{c c c c c c}     
\hline\hline \noalign{\smallskip}                
Sample & Instrument/ & Wavelength          & Spectral                   & Number\\   
 name  &  telescope  & coverage            & resolution                 &  of   \\
       &             & (in $\AA$) & $R=\Delta \lambda/\lambda$ & stars \\
\hline                       
  R09  & RGT/McDonald & 3800--9125  & 60~000 & 63\\   
  M09  & MIKE/Magellan & 3400--10~000 & 65~000 & 42\\
  this & RGT/McDonald, & 3800--9125  & 45~000--& 18\\
  work & HARPS/ESO     & 3783--6865  & 110~000 &  \\
\hline                                  
\end{tabular}
\end{table}