\begin{table}%t1
\caption{Individual measurements. Columns are: (1, 2) date and time of observation; (3, 4)
projected baseline length and position angle (measured East of North); (5)~squared visibility after
calibration and error; (6, 9)~HD~number of calibrators used prior and after the given data point
respectively, 0~means that there was no calibrator; (7, 8, 10, 11)~quantities used for computing
the correlation matrix as in Eq.~(26) of \citet{Perrin03}: $\sigma_{V^2}$ are errors on the
estimated visibility of the calibrators.} \label{tab:obs} 
%\centering
\small
\begin{tabular}{ccccccccccc}
\hline\hline 
\noalign{\smallskip}
& & Projected & Position & Calibrated $V^2$ &  &  &  &  &
\\ Date & UT & baseline (m) & angle ($\degr$) & ($\times 100$) & HD$_a$ & $\alpha$ &
$\sigma_{V^2_a}$ & HD$_b$ & $\beta$ & $\sigma_{V^2_b}$
\\ 
\noalign{\smallskip}
\hline
  2005/05/21
   & 06:17 & 101.60 &  $-$76.85 & $20.4 \pm 1.14$ &      0 & 0.000 & 0.000 & 165683 & 0.330 & 0.870
\\ & 07:31 & 127.86 &  $-$90.04 & $ 6.1 \pm 0.25$ & 176527 & 0.050 & 0.870 & 176527 & 0.060 & 1.025
\\ & 08:20 & 141.07 &  $-$97.43 & $ 2.6 \pm 0.08$ & 176527 & 0.026 & 1.025 & 173780 & 0.039 & 0.896
\\ & 08:59 & 148.55 & $-$102.96 & $ 1.3 \pm 0.04$ & 173780 & 0.024 & 0.896 & 173780 & 0.017 & 0.895
\\ 2005/05/22
   & 06:05 &  98.63 &  $-$75.25 & $23.2 \pm 0.22$ & 159501 & 0.240 & 0.467 & 159501 & 0.064 & 0.624
\\ & 06:24 & 105.77 &  $-$79.02 & $18.2 \pm 0.20$ & 159501 & 0.142 & 0.467 & 159501 & 0.101 & 0.624
\\ & 06:29 & 107.70 &  $-$80.00 & $16.8 \pm 0.18$ & 159501 & 0.120 & 0.467 & 159501 & 0.107 & 0.624
\\ & 06:39 & 111.61 &  $-$81.97 & $14.4 \pm 0.15$ & 159501 & 0.082 & 0.467 & 159501 & 0.115 & 0.624
\\ & 06:49 & 115.39 &  $-$83.83 & $12.2 \pm 0.14$ & 159501 & 0.052 & 0.467 & 159501 & 0.117 & 0.624
\\ & 06:59 & 118.79 &  $-$85.51 & $10.4 \pm 0.12$ & 159501 & 0.030 & 0.467 & 159501 & 0.115 & 0.624
\\ & 08:18 & 141.45 &  $-$97.68 & $ 2.6 \pm 0.07$ & 173780 & 0.014 & 0.624 & 173780 & 0.051 & 0.897
\\ & 08:23 & 142.62 &  $-$98.45 & $ 2.4 \pm 0.06$ & 173780 & 0.011 & 0.624 & 173780 & 0.051 & 0.897
\\ & 08:34 & 144.75 &  $-$99.93 & $ 2.0 \pm 0.06$ & 173780 & 0.005 & 0.624 & 173780 & 0.049 & 0.897
\\ 2005/06/13
   & 05:22 &  33.59 &   20.55 & $84.2 \pm 1.42$ & 168775 & 0.543 & 0.152 & 168775 & 0.362 & 0.153
\\ & 06:15 &  33.85 &   13.58 & $83.4 \pm 0.92$ & 168775 & 0.269 & 0.153 & 168775 & 0.628 & 0.153
\\ & 06:46 &  33.92 &    9.33 & $84.5 \pm 0.73$ & 168775 & 0.419 & 0.153 & 163770 & 0.523 & 0.272
\\ & 07:14 &  33.96 &    5.49 & $80.8 \pm 0.99$ & 163770 & 0.510 & 0.272 & 163770 & 0.419 & 0.272
\\ & 07:43 &  33.97 &    1.37 & $82.8 \pm 1.35$ & 163770 & 0.514 & 0.272 & 163770 & 0.438 & 0.272
\\ & 08:13 &  33.97 &   $-$2.95 & $84.5 \pm 1.19$ & 163770 & 0.833 & 0.272 & 168775 & 0.129 & 0.152
\\ & 09:37 &  33.82 &  $-$14.54 & $83.6 \pm 0.67$ & 163770 & 0.123 & 0.272 & 168775 & 0.784 & 0.152
\\ & 10:04 &  33.70 &  $-$18.05 & $83.9 \pm 0.66$ & 168775 & 0.574 & 0.152 & 176670 & 0.330 & 0.167
\\ 2005/06/14
   & 07:58 &  33.98 &   $-$1.26 & $85.0 \pm 0.90$ & 176670 & 0.521 & 0.166 & 176670 & 0.400 & 0.166
\\ 2005/06/15
   & 06:03 &  33.83 &   14.15 & $84.4 \pm 1.16$ & 176670 & 0.458 & 0.167 & 176670 & 0.457 & 0.167
\\ & 06:39 &  33.92 &    9.18 & $86.5 \pm 1.35$ & 176670 & 0.363 & 0.167 & 176670 & 0.575 & 0.166
\\ & 07:07 &  33.96 &    5.37 & $84.2 \pm 1.41$ & 176670 & 0.544 & 0.166 & 163770 & 0.392 & 0.272
\\ \hline
\end{tabular}
\end{table}