\begin{table}%t3 %\centering \par \caption{\label{tab:var_time}HST-1 variability timescale and characteristic size during the rise and fall of the 2005 flare.} \begin{tabular}{lcccc} \hline\hline \noalign{\smallskip} Wavelength & $\tau_{{\rm rise}}$ & $\tau_{{\rm fall}}$ & $\theta_{{\rm rise}}$ & $\theta_{{\rm fall}}$ \\ &\scriptsize{[yr]} & \scriptsize{[yr]} & \scriptsize{[mas]} & \scriptsize{[mas]} \\ \hline VLA $\lambda$2~cm & 1.5 & 4.9 & 8.7~$\delta$\tablefootmark{a} & 28~$\delta$ \\ VLBA $\lambda$2~cm (beam A) & 1.0 & 4.2 & 5.6~$\delta$ & 24~$\delta$ \\ VLBA $\lambda$2~cm (beam B) & 1.0 & 2.7 & 5.7~$\delta$ & 15~$\delta$ \\ \hline \end{tabular} \tablefoot{ \tablefoottext{a}{The characteristic size is related to the Doppler factor $\delta$.}} \end{table}