\begin{table}%t2
           \caption{\label{tab2}Radial spectral fitting -- best fit values and
associated error bars (90\% confidence level). }
$$ 
         \begin{tabular}{ccccl}
         \hline
         \hline
        ~$R_{\rm out}$~$^{{a}}$ &~$\nh$ &~$kT$ &~$Z$ &~$\chi_{\rm
         red}^{2}$ (d.o.f.)  \\
         (arcmin) & ($10^{21}$~cm$^{-2}$) & (keV) &  ($Z_\odot$)  \\
         \hline
0.14 & 3.00~$\pm$~0.10 & 3.60~$\pm$~0.10 & 0.43~$\pm$~0.05 & 1.04 (1140)\\
0.41 & 2.97~$\pm$~0.05 & 4.54~$\pm$~0.07 & 0.38~$\pm$~0.02 & 1.08 (1979) \\
0.69 & 2.85~$\pm$~0.05 & 5.60~$\pm$~0.10 & 0.32~$\pm$~0.02 & 1.03 (2111)\\
1.02 & 2.81~$\pm$~0.05 & 5.88~$\pm$~0.11 & 0.31~$\pm$~0.02 & 1.09 (2135) \\
1.40 & 2.82~$\pm$~0.05 & 6.21~$\pm$~0.14 & 0.32~$\pm$~0.02 & 1.03 (2052)\\
1.84 & 2.81~$\pm$~0.05 & 6.32~$\pm$~0.16 & 0.28~$\pm$~0.02 & 1.02 (1937)\\
2.34 & 2.77~$\pm$~0.06 & 6.50~$\pm$~0.17 & 0.28~$\pm$~0.03 & 1.01 (1926)\\
2.94 & 2.68~$\pm$~0.06 & 6.67~$\pm$~0.20 & 0.28~$\pm$~0.03 & 1.04 (1736)\\
3.66 & 2.54~$\pm$~0.07 & 6.80~$\pm$~0.25 & 0.24~$\pm$~0.04 & 0.97 (1559)\\
4.54 & 2.41~$\pm$~0.08 & 6.91~$\pm$~0.30 & 0.26$^{{b}}$ & 1.00
(1405)\\
5.64 & 2.39~$\pm$~0.10 & 6.53~$\pm$~0.39 & 0.26$^{{b}}$ & 0.98
(1153)\\
7.01 & 2.01~$\pm$~0.14 & 6.46~$\pm$~0.58 & 0.26$^{{b}}$ & 0.88
(843)\\
12.0 & 1.68~$\pm$~0.22 & 7.04~$\pm$~1.29 & 0.26$^{{b}}$ & 0.90
(443)\\
         \hline
\par
               \end{tabular}
       $$
\smallskip
$\:\:\:\:\:\:^{{a}}$ External radius of the annuli, $^{{b}}$ fixed
parameter.
\par
        \end{table}