\begin{table}%t1
\caption{Log of the observations presented in this paper.\label{tab4}}
%\centerline
{\begin{tabular}{lccc} 
\hline \hline
Satellite & Start time & Exposure time & Count rate \\
& & (ks) & ($10^{-2}$~s$^{-1}$) \\ \hline
ASCA & 28-Oct.-1994 & 36$^a$/44$^b$ & $7.2 \pm 0.2$$^a$/$3.63 \pm 0.13$$^b$\\
{\it Chandra}/ACIS-I & 11-Sep.-2000 & 25 & $8.1 \pm 0.2$ \\
BeppoSAX & 19-Jul.-2001 & 28$^c$/80$^d$/72$^e$ & $2.78 \pm 0.12$$^c$/$5.55 \pm 0.09$$^d$/$13 \pm 4$$^e$ \\  
\hline
\end{tabular}}
\par
\smallskip
\noindent
\hspace*{3.3cm}$^a$~SIS0,
\noindent
$^b$~GIS2,
\noindent
$^c$~LECS,
\noindent
$^d$~MECS,
\noindent
$^e$~PDS.
\end{table}