\begin{table}%t1
%\centering
\par
\caption{\label{tab1}Summary of the \textit{Herschel} telescope characteristics.}
\begin{tabular}{lccccc}
\hline\hline
\noalign{\smallskip}
Line & Band & DSB $T_{\rm sys} $ & HPBW & $T_{\rm mb}/T_{\rm a}$ &
Cal.\ uncert.\ \\ 
\hline
6--5      & 2 & 130 K  & 31$\arcsec$ & 1.4 & 10\% \\
\trece\ 10--9 & 4 & 400 K  & 20$\arcsec$ & 1.4 & 20\%  \\
\doce\ 10--9  & 5 & 800 K  & 20$\arcsec$ & 1.4 & 15\% \\
16--15        & 7 & 1300 K & 12$\arcsec$ & 1.5 & 30\% \\
\hline
\vspace{-4mm}
\end{tabular}
\end{table}