\begin{table}%t2
\caption{Summary of the spectral results in the 0.8--10 keV energy
range. Errors are given at the 90\% confidence level. \label{fits}}
%\centerline
 {
\begin{tabular}[c] {cccccccc}
\hline\hline
\noalign{\smallskip}
Obs. & Model & $N_{\rm H}$ & $\Gamma$ & $k_{\rm B} T$ & $R_{\rm bb}$$^a$& Flux$^b$ & $\chi^{2}_{\rm r}$ (d.o.f.) \\
& &  ($10^{22}$ $\rm cm^{-2}$) & & (keV) & (km) & ($10^{-11}$ erg cm$^{-2}$ s$^{-1}$) & \\
\hline
 %----------------------------------------------------------------------------
A & PL  & $1.4\pm0.2$ & $1.9\pm0.1$ & -- & -- & $\rm 0.92^{+0.04}_{-0.03}$ & 1.60 (98) \\
 & PL+BB  & $\rm 1.6^{+0.6}_{-0.4}$ & $\rm 0.9^{+0.3}_{-0.4}$ & $0.5\pm0.1$ & $\rm 4^{+2}_{-1}$ & $1.0\pm0.1$ & 1.12 (96) \\
 & PL+BB  & 2.6 (fixed) & $\rm 1.1^{+0.3}_{-0.2}$ & $\rm 0.44^{+0.03}_{-0.05}$ & $\rm 7^{+2}_{-1}$ & $1.11\pm0.06$ & 1.16 (97) \\
 %----------------------------------------------------------------------------
B & PL  & $2.4\pm0.2$ & $2.2\pm0.1$ & -- & -- & $2.6\pm0.1$ & 1.22 (113) \\
 & PL+BB  & $\rm 1.7^{+0.6}_{-0.5}$ & $\rm 1.5^{+0.5}_{-0.6}$ & $0.7\pm0.1$ & $3\pm1$ & $2.5\pm0.2$ & 1.16 (111) \\
 & PL+BB  & 2.6 (fixed) & $2.0\pm0.2$ & $0.5\pm0.1$ & $5\pm2$ & $2.7\pm0.2$ & 1.21 (112) \\
 %----------------------------------------------------------------------------
C & PL  & $\rm 2.0^{+0.4}_{-0.3}$ & $2.3\pm0.1$ & -- & -- & $0.95\pm0.04$ & 1.29 (84) \\
 & PL+BB  & $2\pm1$ & $\rm 1.7^{+0.3}_{-0.6}$ & $0.5\pm0.1$ & $\rm 5^{+7}_{-2}$ & $\rm 1.0^{+0.1}_{-0.2}$ & 1.09 (82) \\
 & PL+BB  & 2.6 (fixed) & $1.7\pm0.3$ & $0.45\pm0.05$ & $\rm 6^{+2}_{-1}$ & $1.1\pm0.1$ & 1.08 (83) \\
 %----------------------------------------------------------------------------
 D & PL  & $2.1\pm0.3$ & $2.4\pm0.1$ & -- & -- & $0.90\pm0.05$ & 1.06 (83) \\
 & PL+BB  & $\rm 2.2^{+0.9}_{-0.7}$ & $\rm 2.0^{+0.4}_{-0.5}$ & $0.5\pm0.1$ & $\rm 4^{+8}_{-2}$ & $\rm 0.9^{+0.1}_{-0.2}$ & 1.00 (81) \\
 & PL+BB  & 2.6 (fixed) & $2.1\pm0.3$ & $0.4\pm0.1$ & $\rm 7^{+4}_{-2}$ & $1.0\pm0.1$ & 0.99 (82) \\
 %----------------------------------------------------------------------------
 E & PL  & $3.6\pm0.2$ & $2.2\pm0.1$ & -- & -- & $3.5\pm0.1$ & 1.18 (121) \\
 & PL+BB  & $\rm 2.6^{+0.7}_{-0.9}$ & $\rm 1.8^{+0.3}_{-0.8}$ & $\rm 0.9^{+0.2}_{-0.1}$ & $\rm 1.6^{+0.6}_{-0.8}$ & $\rm 3.1^{+0.3}_{-0.2}$ & 1.13 (119) \\
 & PL+BB  & 2.6 (fixed) & $\rm 1.7^{+0.1}_{-0.2}$ & $0.9\pm0.1$ & $\rm 1.7^{+0.4}_{-0.5}$ & $3.1\pm0.2$ & 1.12 (120) \\
 %----------------------------------------------------------------------------
 F & PL  & $\rm 2.4^{+0.3}_{-0.2}$ & $2.3\pm0.1$ & -- & -- & $\rm 1.06^{+0.04}_{-0.03}$ & 1.35 (105) \\
 & PL+BB  & $\rm 2.4^{+0.8}_{-0.5}$ & $1.4\pm0.4$ & $0.5\pm0.1$ & $\rm 5^{+3}_{-1}$ & $\rm 1.1^{+0.1}_{-0.2}$ & 1.06 (103) \\
 & PL+BB  & 2.6 (fixed) & $1.5\pm0.3$ & $\rm 0.51^{+0.03}_{-0.05}$ & $5\pm1$ & $1.1\pm0.1$ & 1.05 (104) \\
 %----------------------------------------------------------------------------
 I & PL  & $1.9\pm0.3$ & $2.4\pm0.1$ & -- & -- & $0.62\pm0.03$ & 1.06 (94) \\
 & PL+BB  & $3\pm1$ & $2.2\pm0.3$ & $0.3\pm0.1$ & $\rm 8^{+25}_{-4}$ & $\rm 0.73^{+0.04}_{-0.09}$ & 0.94 (92) \\
 & PL+BB  & 2.6 (fixed) & $2.1\pm0.2$ & $\rm 0.37^{+0.04}_{-0.06}$ & $\rm 8^{+4}_{-2}$ & $0.69\pm0.04$ & 0.93 (93) \\
 %----------------------------------------------------------------------------
 \hline
\end{tabular}}
\par
\smallskip
$^a$ Radius at infinity assuming a distance of 15 kpc. 
$^b$ Flux in the 2--10 keV range, corrected for the absorption.
\par
\end{table}