\begin{table}%T2
\caption{Approximation of observed brightness profiles of Galactic ridge emission in two energy bands.}
\label{prof_param}
%\centerline
{
\begin{tabular}{l|cc|cc}\hline\hline
Par.&\multicolumn{2}{c}{Epoch4}&\multicolumn{2}{|c}{Epoch5}\\
\hline
         & 3--20 keV& 10--20 keV& 3--20 keV&10--20 keV\\
\hline
$b_0$&$3.30\pm 0.58$&$3.27\pm1.28$&$3.25\pm 0.71$&$3.26\pm1.78$\\
Norm$^a$&$4.53\pm 0.42$&$0.45\pm0.09$&$4.73\pm0.52$&$0.68\pm0.18$\\
\hline
\end{tabular}}
\par
\medskip
$^a$ Normalization in counts/s/PCU. 1 count/s/PCU corresponds
approximately to $1.2\times 10^{-11}$, $2.3\times 10^{-11}$ and $10^{-10}$~erg/s/cm$^2$ in 3--20 keV, 10--20 keV and 20--30 keV energy bands correspondingly.
\end{table}