\begin{table}%T3
\caption{Best-fit values for the power-law parameters, when the four spectra are fitted simultaneously with common values of $N_{\rm H}$ ($(6.1^{+0.3}_{-0.1})\times10^{21}$~cm$^{-2}$), $kT_{\rm BB}$ ($1.40^{+0.02}_{-0.04}$~keV) and $R_{\rm BB}$ ($111^{+1}_{-4}$~m). Errors are at 90\% confidence level for a single interesting parameter.}\label{4spectra_BBcommon}
%\centerline
{\small
\begin{tabular}{c|cccc} \hline\hline
Spectral            &   \multicolumn{4}{c}{Phase Interval}                                          \\
Parameter           &   A           &   B           &   C           &   D           \\ \hline
$\Gamma$   &   $\rm 1.98^{+0.03}_{-0.04}$  &   $\rm 1.57^{+0.02}_{-0.02}$  &   $\rm 1.56^{+0.04}_{-0.03}$   &   $\rm 2.63^{+0.13}_{-0.08}$  \\
$I_{\rm PL}^{a}$    &   $\rm 2.40^{+0.06}_{-0.06}$  &   $\rm 3.47^{+0.05}_{-0.04}$   &   $\rm 1.39^{+0.03}_{-0.05}$  &   $\rm 0.97^{+0.04}_{-0.05}$  \\
$f_{\rm TOT}^{b}$       &   2.08        &   3.43        &   1.81        &   1.19        \\
$f_{\rm PL}^{b}$        &   1.36    &   2.71    &   1.09    &   0.47     \\
 & (65\%) & (79\%) & (60\%) & (40\%) \\
$f_{\rm BB}^{b}$        &   0.72    &   0.72    &   0.72    &   0.72     \\
 & (35\%) & (21\%) & (40\%) & (60\%) \\ \hline
\end{tabular}}
\medskip
$^{a}$ Intensity of the power-law component in units of $10^{-3}$~ph~cm$^{-2}$~s$^{-1}$~keV$^{-1}$ at 1~keV.\\
$^{b}$ Unabsorbed flux in the energy range 0.3$-$10~keV, in units of $10^{-11}$~erg~cm$^{-2}$~s$^{-1}$.
\end{table}