\begin{table}%t1
%\centering
\par
  \caption {\label{tab:parameters}Expected system parameters of FAST and the pulsar survey.}
  \begin{tabular}{ll}
    \hline
    \hline
    Parameter                     & Value \\
    \hline
    Gain                          & 16.5~KJy$^{-1}$ \\
    System temperature 19-beam receiver   & 20~K \\
    System temperature 100-beam receiver  &30~K \\
    Centre frequency              & 1315~MHz \\
    Bandwidth                     & 400~MHz \\
    Number of frequency channels  & 9500 \\
    No. of polarisations          & 2 \\
    Beam FWHM                     & 3$^\prime$.4 \\
    No. of beams                  & 19 or 100 \\
    \hline
  \end{tabular}
\end{table}