\begin{table}%t2
%\centering
\par
\caption {\label{tab:pnfits}The spectral parameters derived from the \xmm\ EPIC pn observations, with the relative phase coverage. The reported flux is measured in a 0.3--7.0~keV band.}
\begin{tabular}{lrrrr}
\hline\hline
Obs. & 201 & 301 & 401 & 501 \\\hline
Start date & 2005-07-27 & 2005-07-29 & 2005-08-02 & 2005-08-06 \\
Start time (UT) & 04:07:27 & 01:36:19 & 05:53:00 & 05:10:42 \\
Obs. duration (s) & 39~234 &  41~030 & 42~504 & 38~170 \\
$\phi$ begin & 0.03 & 0.19 & 0.54 & 0.87 \\
$\phi$ end    & 0.07 & 0.23 & 0.58 & 0.91 \\
$N({\rm H})$ ($10^{20}$ cm$^{-2}$) & $4.5\pm0.1$ & $5.2\pm0.2$ & $3.2\pm0.1$ & $5.8\pm0.2$ \\
$T_1$	(keV) & $0.23\pm0.06$ 	& $0.24\pm0.01$	& $0.29\pm0.01$	& $0.24\pm0.01$\\
$T_2$	(keV) & $0.69\pm0.03$	& $1.14\pm0.1$	& $2.0\pm1.4$	& $0.63\pm0.02$\\
$EM_1$ ($10^{53}$ cm$^{-3}$)	& $12.0\pm5.0$	& $18.8\pm6.4$	& $16.0\pm4.2$ & $17.2\pm6.4$\\
$EM_2$ ($10^{53}$ cm$^{-3}$)	& $0.96\pm0.42$	& $0.45\pm0.12$	& $0.14\pm0.20$ & $0.83\pm0.42$\\
flux($10^{-12}$ erg cm$^{-2}$ s$^{-1}$)	& 1.01	& 0.89	& 0.99	& 0.92\\
O/O$_\odot$ & $0.13\pm0.03$	& $0.08\pm0.02$	& $0.08\pm0.02$	& $0.09\pm0.02$\\
Ne/Ne$_\odot$ & $0.18\pm0.05$	& $0.22\pm0.06$	& $0.16\pm0.03$	& $0.16\pm0.03$\\
Si/Si$_\odot$ & $0.72\pm0.24$	& $0.23\pm0.13$	& $0.40\pm0.13$	& $0.41\pm0.16$\\
Fe/Fe$_\odot$ & $0.45\pm0.13$	& $0.28\pm0.08$	& $0.17\pm0.03$	& $0.32\pm0.08$\\\hline
\end{tabular}
\end{table}