\begin{table}%t6
\caption{\label{t:fe_var} Parameters of the \fek\ at different epochs.}
%\centerline
{\begin{tabular}{llll}
\hline
\hline\noalign{\smallskip}
Year & $E$ & $L$ & {\it FWHM}\\
& (keV) & (10$^{40} $erg~s$^{-1}$) & (keV)\\
\hline
2002a & $6.43\pm0.03$ & $46\pm11$ & $0.26\pm0.12$\\
2002b & $6.42\pm0.04$ & $41\pm15$ & $<$0.20\\ 
2005 obs 1 & $6.42\pm0.01$ & $56\pm8$ & $0.19\pm0.05$\\ 
2005 obs 2 &$6.40\pm0.02$ & $53\pm8$ & $0.17\pm0.05$\\
2005 obs 3 & $6.42\pm0.03$ & $86\pm17$ & $0.3\pm0.1$\\
\hline
\end{tabular}}
\par
\tablefoot{We list the energy, intrinsic luminosity and {\it FWHM} 
for a single-line fit to the \fek\ profile for the spectra obtained in
2005 in three separate orbits and for observations collected in 2002 by \xmm\ (2002a) and \ch-HETGS (2002b).}%\vspace*{3.5mm}
\end{table}