\begin{table}%t1
%\centering
\par
\caption{Predicted temporal slopes $\alpha$ for various afterglow scenarios
based on the measured spectral slopes  $\beta_{\rm opt}=0.64 \pm 0.03$
(Sect.~\ref{sec:sedz}) and  $\beta_{\rm X} = 1.01^{+0.28}_{-0.25}$
(Sect.~\ref{sec:x-aft}).  These values have to be compared with the measured
$\alpha_{\rm opt}=1.67\pm0.07$ and $\alpha_{\rm X}=1.52\pm0.14$.  Assuming a
jet, for $t<t_{\rm break}$ the isotropic model holds, whereas for $t>t_{\rm
break}$  the jet model applies (e.g. Zhang \& M\'esz\'aros \cite{Zhang2004}). The
$\sigma$-level represents the difference between the predicted and the
observed temporal slope, normalized to the square root of the sum of their
quadratic errors. The favoured model is highlighted.}\label{table:alphabeta}
\small \begin{tabular}{lcccr}
\hline\hline
 Afterglow model & \multicolumn{2}{c}{Optical}& \multicolumn{2}{c}{\mbox{X-ray}}\\ &
$\alpha_{\rm opt}$ & $\sigma$-level & $\alpha_{\rm X}$& $\sigma$-level\\
\hline
\multicolumn{5}{c}{Iso}\\ 
ISM, wind,$\nu_{\rm c}<\nu$ & $0.46\pm0.05$&$-14.54$ &$\rm 1.02^{+0.42}_{-0.38}$ &$-1.14$  \\ 
ISM, $\nu<\nu_{\rm c}$   & $0.96\pm0.05$  &$-8.53$ &$\rm 1.52^{+0.42}_{-0.38}$ &$-0.01$ \\ 
\textbf{wind}, $\nu<\nu_{\rm c}$     & $1.46\pm0.05$  &$-2.52$ &$\rm 2.02^{+0.42}_{-0.38}$ &$1.24$ \\ 
\hline \multicolumn{5}{c}{Jet}\\ 
ISM, wind, $\nu_{\rm c}<\nu$& $1.28\pm0.06$  &$-4.23$ &$\rm 2.02^{+0.56}_{-0.50}$ &$0.96$  \\ 
ISM, wind, $\nu<\nu_{\rm c}$& $2.28\pm0.06$  &$6.62$ &$\rm 3.02^{+0.56}_{-0.50}$ &$2.89$ \\ 
\hline
\end{tabular}
\end{table}