\begin{table}%t3
\caption{\label{specpersist}\xmm/PN and \swift/XRT spectral results for the persistent emission.}
%\centerline
 {\tiny  
\begin{tabular}{lcccc}
\hline \hline\noalign{\smallskip}
Date$^a$& $N_{\rm H}$$^b$ & $\Gamma$ & $F_{\rm pers}$$^c$ & $\chi^2/{\rm d.o.f.}$ \\
~ & [10$^{22}$ cm$^{-2}$] & ~ & ~  & ~ \\
\hline
&   & \xmm/PN   &   &    \\
%\hline
2002 Oct. 3 & $14\pm3$	 & $2.0\pm0.5$	 & $1.0\pm0.2$  & $67/64$\\
~ & $[11.9]$ & $1.6\pm0.2$ & $0.9\pm0.2$ & $68/65$\\
2007 Feb. 27	& $11.9\pm0.2$	& $1.83\pm0.03$	& $11.60\pm0.05$ 	& $219/197$\\
2007 Mar. 30	& $11.6\pm0.4$	& $1.76\pm0.08$	& $11.9\pm0.1$ 	& $155/200$\\
~			& $[11.9]$			& 1.81$\pm0.04$	& $12.2\pm0.1$ 	& $156/201$\\
2007 Mar. 31	& $12.1\pm0.4$	& $1.86\pm0.08$	& $12.0\pm0.1$ 	& $192/210$\\
~			& $[11.9]$			& $1.83\pm0.04$	& $11.9\pm0.1$ 	& $192/211$\\
2007 Apr. 1	& $12.0\pm0.3$	& $2.08\pm0.05$	& $13.6\pm0.1$ 	& $242/213$\\
~			& $[11.9]$			& $2.06\pm0.02$	& $13.5\pm0.1$ 	& $242/214$\\
2007 Apr. 2	& $12.5\pm0.3$	& $2.14\pm0.05$	& $13.1\pm0.1$ 	& $213/195$\\
~			& $[11.9]$			& $2.04\pm0.02$	& $12.4\pm0.1$ 	& $225/196$\\
2007 Apr. 3--4	& $13.1\pm0.4$	& $2.30\pm0.08$	& $5.5\pm0.1$ 		& $179/200$\\
~			& $[11.9]$			& $2.08\pm0.03$	& $4.9\pm0.1$ 		& $204/201$\\
\hline
&                          & \swift/XRT                                                               &              &                   \\
%\hline
2007 Feb. 16--17 & $10.9\pm3.6$	& $1.9\pm0.7$		& $19.0\pm3.0$ 		& $31/28$\\
\hline
\end{tabular}}
\medskip
$^a$~For 2007, Mar. 30 and 31 designate the periods just before and after burst~12 respectively (see Fig.~\ref{lc_pn}). Same thing for Apr.~1 and~2 and burst 13. Apr.~3--4 period is the last \xmm~revolution (rev-1340); $^b$~whenever there are brackets, the column density is frozen; $^c$~unabsorbed flux in the 2--8~keV and 2--10~keV band in units of 10$^{-11}$ \ergperseccm~for \xmm/PN and \swift/XRT, respectively. 
\end{table}