\begin{table}%T4
 \caption{\label{tab:grb080506_x}Decay and spectral index of the \mbox{X-ray} afterglow of GRB~080506.}
\small
%\centering
\par
\begin{tabular}{cccc}
\hline\hline\noalign{\smallskip}
Region & $T$ (s)& $\alpha_{\rm X}$\tablefootmark{\dag}($\chi^2$/d.o.f.) & $\beta_{\rm X}$\tablefootmark{\ddag}  \\ 
\hline
{Prompt Emission} & 145--200 & prompt like                & $-$0.38 $\pm$ 0.03 \\ 
{Steep Decay}& 200--350     & $-$4.8 $\pm$0.2(43.3/30)    & $-$1.05 $\pm$ 0.06 \\ 
{Flare Rise} & 350--474     & 10.14 $\pm$0.72(23.8/6)     & $-$0.80 $\pm$ 0.18  \\
{Flare Peak} & 474--503     &      --	                 & $-$1.02 $\pm$ 0.13  \\
{Flare Decay}& 503--672     & $-$6.41 $\pm$0.24(50.9/47)  & $-$1.49 $\pm$ 0.10  \\
{Normal Decay}  & 10~900--70~300  & $-$0.81 $\pm$0.05 (55.7/19) & $-$1.26$_{-0.16}^{+0.17}$ \\ \hline\end{tabular}
\tablefoot{The uncertainties show the 90\% confidence levels of the parameters. 
       \tablefoottext{\dag}{\mbox{X-ray} decay index.}
       \tablefoottext{\ddag}{\mbox{X-ray} spectral index($\chi^2$/d.o.f. = 587.7/298).}
     }
\end{table}