\begin{table}%t2
\caption{\label{table1}Telescope parameters.}
%\centering
\par
\begin{tabular}{l l l l l}
\hline\hline\noalign{\smallskip}
Frequency [GHz]& 119& 480& 540& 580 \\
\noalign{\smallskip}\hline\noalign{\smallskip}
Beam size [arc min]& 9.96& 2.42& 2.20& 2.05 \\
Aperture efficiency& 0.72& 0.70& 0.69& 0.69 \\
Main beam efficiency& 0.91& 0.89& 0.89& 0.89 \\
\noalign{\smallskip}\hline
\end{tabular}
\end{table}