\begin{table}%T6
\caption{\label{tab:joint2}Predicted spectral slope $\beta$  considering the parameters  listed 
in Table~\ref{tab:joint1}
for different applied models. The spectral slopes have to be  compared with
the observed $\beta_{\rm X} = 1.06\pm0.16$ (Sect.~\ref{xray}).}
\small%\centering
\par
\begin{tabular}{lll}
\hline\hline
\textbf{Model}      & $\beta\left(\alpha\right)$   &  value \\
\hline
\multicolumn{3}{l}{Fast cooling}\\
%\midrule
 ISM$_{\rm iso}$   & $(2\alpha^{\rm X} _1 +1)/3$  & $1.36\pm0.07$\\
 ISM$_{\rm jet}$   & $\alpha_2 /2$	      & $1.28\pm0.07$\\
wind$_{\rm iso}$        & $(2\alpha^{\rm X} _1 +1)/3$  & $1.36\pm0.07$\\
wind$_{\rm jet}$        & $\alpha_2 /2$                & $1.28\pm0.07$\\
%\midrule
\multicolumn{3}{l}{Slow cooling}\\
%\midrule
  ISM$_{\rm iso}$   & $2\alpha^{\rm X} _1 / 3$     & $1.03\pm0.07$\\
  ISM$_{\rm jet}$   & $(\alpha_2 -1)/2$	       & $0.78\pm0.07$\\
      wind$_{\rm iso}$  & $(2\alpha^{\rm X}_1 -1)/ 3$  & $0.69\pm0.07$\\
      wind$_{\rm jet}$  & $(\alpha _2 -1)/ 3$          & $0.78\pm0.07$\\
\hline
\end{tabular}
\end{table}