\begin{table}%t1
%%\centering
\par
\caption{Residual error (radius) on the positions (at the center, on average, and at the border of
  the partially coded field of view) corrected for the misalignment. As the SPI analysis is based 
  on groups of pointings, only the mean value is given.}
\label{restab}
\begin{tabular}{lccc}
\hline\hline
Instrument & &Position residuals&   \\
                    & On-axis & Mean& Edge of the PCFOV \\
\hline
ISGRI  & 15\arcsec & 40\arcsec   & 140\arcsec\\ 
SPI    &           & 40\arcsec   & \\ 
JEM-X  &  4\arcsec & 18\arcsec   &  50\arcsec\\ 
\hline
\end{tabular}
\end{table}