\begin{table}%t1 \caption{Log of the observations\label{log}.} %\centerline {\small\begin{tabular}{llccc} \hline\hline Date/Time & Telescope/Instrument & Filter & Exposure & Brightness \\ (UT in 2008) & & & (min) & (mag)$^{(a)}$ \\ \hline Sep. 17 02:53--03:43 & IRSF/SIRIUS & $JHK_{\rm S}$ & 50.0 & $21.0 \pm 0.5$ / $20.4\pm 0.4$ / $20.3 \pm 0.5$ \\ Sep. 17 07:57--09:39 & MPI/ESO 2.2~m/GROND & $g'r'i'z'$ & 75.0 & $>$23.6 / $22.81 \pm 0.07$ / $22.05 \pm 0.05$ / $21.76\pm0.05$\\ Sep. 17 07:57--09:39 & MPI/ESO 2.2~m/GROND & $JHK_{\rm S}$ & 60.0 & $21.50 \pm 0.06$ / $21.29 \pm 0.08$ / $21.10 \pm 0.15$\\ Sep. 19 08:04--09:42 & MPI/ESO 2.2~m/GROND & $g'r'i'z'$ & 79.4 & $>$23.6 / $>$23.8 / $23.47 \pm 0.13$ / $>$23.8\\ Sep. 19 08:04--09:42 & MPI/ESO 2.2~m/GROND & $JHK_{\rm S}$ & 64.0 & $>$21.9 / $>$21.2 / $>$20.5\\ Sep. 20 08:42--09:42 & MPI/ESO 2.2~m/GROND & $g'r'i'z'$ & 50.0 & $>$23.9 / $>$24.2 / $23.78 \pm 0.16$ / $>$23.8\\ Sep. 20 08:42--09:42 & MPI/ESO 2.2~m/GROND & $JHK_{\rm S}$ & 40.0 & $>$22.5 / $>$21.5 / $>$20.6\\ Sep. 24 07:32--09:31 & MPI/ESO 2.2~m/GROND & $g'r'i'z'$ & 100.1~~ & $>$25.0 / $>$24.5 / $>$24.3 / $>$23.9\\ Sep. 24 07:32--09:31 & MPI/ESO 2.2~m/GROND & $JHK_{\rm S}$ & 74.2 & $>$22.2 / $>$21.5 / $>$20.8\\ Oct. 29 07:59--08:31 & Gemini-S/GMOS & $i'$ & 24.0 & $>$25.1\\ \hline \end{tabular}} \medskip $^{(a)}$ Not corrected for Galactic foreground reddening of $E(B-V) = 0.32$~mag (Schlegel et~al. \cite{Schlegel1998}). All magnitudes are given in the AB~system. \end{table}