\begin{table}%t1 \caption{\label{tab:log}Log of the spectroscopic observations with VLT/VISIR.} \small \begin{tabular}{lcccr} \hline\hline Target & Slit & Observing date & Airmass & $T_{\rm int}$ \\ \hline T-Tau & slit 1 & 03.02.2008 \ \ 00:34 & 1.42 & 800 \\ HD-28305 & slit 1 & 03.02.2008 \ \ 01:20 & 1.48 & 800 \\ T-Tau & slit 3 & 04.02.2008 \ \ 00:34 & 1.43 & 960 \\ HD-28305 & slit 3 & 04.02.2008 \ \ 01:26 & 1.51 & 800 \\ HD-28305 & slit 2 & 07.02.2008 \ \ 00:41 & 1.43 & 800 \\ T-Tau & slit 2 & 07.02.2008 \ \ 01:23 & 1.59 & 1040 \\ \hline \end{tabular} \end{table}