\begin{table}%t1
  \caption{Principal parameters of the CANGAROO-II telescope.}
  \label{tab:mainpara}
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\par
     \begin{tabular}{ll}
        \hline
        \hline
        Parameters & Values\\
        \hline
       Location  & 136 $^\circ$E, 31 $^\circ$S \\
	Height above sea level & 220~m \\
	Total diameter & 10~m \\
	Focal length   & 8~m \\
	Number of segmented mirrors  & 114\\
	Mirror diameter & 80~cm \\
	Mirror segment shape & Spherical\\
	Mirror alignment & Parabolic\\
	Mirror curvature & 16.4~m\\
	Mirror material & Plastic (CFRP)\\
        \hline
     \end{tabular}
\end{table}