\begin{table}%T1
\par
%\centering
\par
\caption{Log of the observations. $\sigma_{{\rm star}}$ denotes
  the standard deviation of flux in images of the guide star during each
  integration. Column 6
  lists the signal to noise ratio of a one-dimensional spectrum within
  a 1\arcsec\ radius of the QSO.}
\label{tab:log}
\begin{tabular}{lllllll}
\hline \hline
Date (UT)  & Exposure time (s)& Airmass  &Seeing&
$\sigma_{{\rm star}}$(\%)  & {\it S/N} \\
\hline
 Sep. 5 2002 02:48 &   1800 & 1.19 & 1\arcsec          & 0.5  & 5.9\\
 Sep. 5 2002 03:20 &   1800 & 1.19 & 1\arcsec          & 0.5  & 5.7\\
 Sep. 8 2002 00:03 &   1800 & 1.57 & 1\farcs3--1\farcs5 & 10   & 3.9\\
 Sep. 8 2002 00:36 &   1800 & 1.14 & 1\farcs3--1\farcs5 & 9    & 4.2\\
\hline
\end{tabular}
\end{table}