All Figures

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig1.eps}\end{figure}$ Figure 1: This figure shows 14 afterglow light-curves generated with parameters summarized in Zeh et al. (2005). The bold line and the bold dash-dotted line show the light curves of a typical afterglow ( $\alpha_{1}=1,2~$ , $\alpha _{2}=2$ , $t_{\rm b}=1,5$ days, m₁=20,5, $m_{\rm b}=21$ , $m_{\rm h}=25$ ) without and with a break respectively. The bold dashed line is the fraction of afterglows brighter than 23rd magnitude at a given time (right hand scale). Nearly 90% of the afterglows are visible at magnitude $m\leqslant 23$ , one day after the burst and 50%, 6 days after the burst.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{5599fig2.eps} \end{figure}$ Figure 2: This diagram shows the observational strategy for one field of the Very Wide Survey. Each vertical line stands for one exposure, the exposure time depends on the filter, but is typically of the order of 100 s. 15 new fields or more are observed each month.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{5599fig3.eps} \end{figure}$ Figure 3: This diagram shows the global mechanism of the RTAS pipeline and the interactions between the different components.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig4.eps}\end{figure}$ Figure 4: The upper figure shows our classification of objects in a plot $\mu _{\rm max}$ -magnitude versus $\mu _{\rm max}$ . We construct 4 classes of astrophysical objects: stars (1), galaxies (2), faint objects (3), saturated objects (4), and a class containing cosmic-rays (5). The lower two graphics represent the computation of the $\mu _{\rm max}$ and magnitude completeness respectively.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig5.eps} \end{figure}$ Figure 5: Histogram of the distance separating the nearest objects in two images. The largest peak is due to real astrophysical objects which are detected in the two images. The two vertical lines show the position tolerance and two times the position tolerance used for the matching of objects in the two images.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig6.eps} \end{figure}$ Figure 6: This diagram illustrates the spliting of astrophysical objects in matched, suspect and single objects in triple comparisons.
Open with DEXTER

In the text

$\begin{figure} \par {\hspace*{2.5cm}\includegraphics[width=11.8cm,clip]{5599fig7... ...m}}\vspace*{0.2mm} \includegraphics[width=16.8cm,clip]{5599fig8.eps}\end{figure}$ Figure 7: These two snapshots show two characterized variable stars in double ( top) and triple ( bottom) comparisons. For each images in which the object is detected, a thumbnail around its position is cut, and the difference of magnitude is computed. The coordinates of the first variable star are RA = 09:01:12.39, Dec = +17:29:09.22 and its magnitude in the first image is 20.21. The coordinates of the second variable star are RA = 04:50:40.66, Dec = +21:58:21.28 and its magnitude in the second image is 21.02.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{5599fig9.eps}\end{figure}$ Figure 8: Histogram of the total number of astrophysical objects (solid line), and of the cosmic-ray hits (dashed line) in all the CCD frames studied. The nearly constant number of cosmic-ray hits, about 300 per CCD frame, is explained by the quasi constancy of the exposure time. The number of astrophysical objects, on the other hand appears much more variable as it depends strongly on the filter, and on the galactic latitude of the observations.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.1cm,clip]{5599fi10.eps}\hspace*{2mm} \includegraphics[width=8.1cm,clip]{5599fi11.eps} \end{figure}$ Figure 9: Objects detected variable by our automatic software, in triple ( left) and double ( right) comparisons. Each point represents one object in the comparison of a pair of images. The x-axis shows the median magnitude while the y-axis shows the magnitude difference between the two images. In the triple comparisons each object is represented by three points corresponding to the three possible pairs of images. The distribution of these variable objects is shown to illustrate the domain of sensitivity of our search (in magnitude and $\Delta mag$ ). For comparison we have also shown the track of a typical afterglow ( $\alpha =1.2$ , M₁=21 and $M_{\rm host}=24$ , see Sect. 7), as a function of its age (in days) at the time of the first observation.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=4.3cm,clip]{5599fi12.eps}\hspace*{1.5mm} \includegraphics[width=4.3cm,clip]{5599fi13.eps} \end{figure}$ Figure 10: These two figures show the normalized distributions of $\alpha$ ( left) and M₁ ( right) for 60 observed afterglows and the distribution we choose to fit the data. Since there is no correlation between $\alpha$ and M₁, these values can be drawn independently.
Open with DEXTER

In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{5599fig2.eps} \end{figure}$	Figure 2: This diagram shows the observational strategy for one field of the Very Wide Survey. Each vertical line stands for one exposure, the exposure time depends on the filter, but is typically of the order of 100 s. 15 new fields or more are observed each month.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{5599fig3.eps} \end{figure}$	Figure 3: This diagram shows the global mechanism of the RTAS pipeline and the interactions between the different components.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig5.eps} \end{figure}$	Figure 5: Histogram of the distance separating the nearest objects in two images. The largest peak is due to real astrophysical objects which are detected in the two images. The two vertical lines show the position tolerance and two times the position tolerance used for the matching of objects in the two images.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=8cm,clip]{5599fig6.eps} \end{figure}$	Figure 6: This diagram illustrates the spliting of astrophysical objects in matched, suspect and single objects in triple comparisons.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=4.3cm,clip]{5599fi12.eps}\hspace*{1.5mm} \includegraphics[width=4.3cm,clip]{5599fi13.eps} \end{figure}$	Figure 10: These two figures show the normalized distributions of $\alpha$ ( left) and M₁ ( right) for 60 observed afterglows and the distribution we choose to fit the data. Since there is no correlation between $\alpha$ and M₁, these values can be drawn independently.
Open with DEXTER