\begin{table}%t1 \caption{\label{log}Log of observations and results for GG Car.} %\centerline {\begin{tabular}{lllllll} \hline \hline Date & IT$^{a}$ & \it{S/N}$^{b}$ & $\it{P}_{\rm obs}$$^{c}$ & PA$_{\rm obs}$$^{c}$ & PA$_{\rm int}$ \\ & (s) & & (\%) & (\degr) & (\degr) \\ \hline 2006 Apr. 05 & 4800 & 104 & 1.6 (0.1) & 85 (2) & 84 (6) \\ 2006 May 18 & 4800 & 154 & 1.5 (0.1) & 84 (2) & 85 (4) \\ \hline \end{tabular}} \medskip \par Errors in parenthesis. $^{a}$ Total integration time (8 $\times$ individual integration time by waveplate position); $^{b}$ signal-to-noise ratio per pixel for the unbinned spectra; $^{c}$ mean values for the full~spectrum (6300--6800~$\rm \AA$) binned with a polarization error (per bin) of 0.1\%. The quoted polarization error is the average error per bin and the PA error is given by 28.65$\times\sigma_{P}/P$~\rm(Serkowski~\cite{ser74}). \end{table}