All Figures

$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f1.eps}\end{figure}$ Figure 1: Observations of Q0957+561 with the Liverpool robotic telescope in the g band. We display system subframes ( left panels), model subframes ( middle panels), and residual subframes ( right panels) for five frames taken during the 2.5-year monitoring period (see main text).
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f2.eps}\end{figure}$ Figure 2: Colour coefficient in the g band. The values are distributed around the central discontinuous line (average coefficient), and most of them are placed between the top and bottom discontinuous lines (filled circles). Only seven extreme values (triangles and open circles) exceed these limits.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f3.eps}\end{figure}$ Figure 3: Inhomogeneity map in the g band. The zero inhomogeneity level is described by means of a continuous line that crosses the centre of the $1024\times 1024$ camera. Pixels inside this zero level contour have a positive inhomogeneity of a few mmag, whereas the rest of the pixels have a negative inhomogeneity that varies between a few mmag and tens of mmag. We explicitly show contours of -10, -20, -30, -40, -50, -60, and -70 mmag.
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In the text

$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f4.eps}\end{figure}$ Figure 4: Final magnitudes of Q0957+561A ( top panel) and Q0957+561B ( bottom panel) in the g band of the SDSS photometric system. These g-SDSS light curves include noticeable fluctuations covering a 2.5-year monitoring period from January 2005 to June 2007.
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In the text

$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f5.eps}\end{figure}$ Figure 5: Final magnitudes of Q0957+561A ( top panel) and Q0957+561B ( bottom panel) in the r band of the SDSS photometric system. The r-SDSS records from October 2005 to June 2007 (two whole seasons) incorporate different prominent features that are also seen in the g-SDSS curves (see Fig. 4), with the g-SDSS features having a larger amplitude.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f6.eps}\end{figure}$ Figure 6: Comparison between the g-band light curve of A in the second season (shifted by 420 d; see main text) and the g-band light curve of B in the third season. The A record (filled circles) shows two different features separated by a gap of about 50 d: while the first feature contains an event AE1g and the beginning of another consecutive event AE2g, the second feature describes the (noisy) decline in flux of AE2g. A vertical line is drawn to distinguish between the two events AE1g and AE2g. Replica events BE1g and BE2g are clearly seen in the B record (open circles).
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In the text

$\begin{figure} \par\includegraphics[angle=0,width=9cm]{10447_f7.eps}\end{figure}$ Figure 7: Overlapping periods and difference light curves in the g band. We show the overlap between the A (filled circles) and B (open circles) whole records, when the A magnitudes are shifted by the best solutions of the time delay and the magnitude offset ( left panels). We also draw the difference light curve ( right panels). The three overlap periods cover $\sim$ 20 d ( top panels), $\sim$ 90 d ( middle panels), and $\sim$ 60 d ( bottom panels).
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In the text

$\begin{figure} \par\includegraphics[angle=0,width=9cm]{10447_f8.eps}\end{figure}$ Figure 8: Comparison between the DCF (filled circles) and the $\langle DAF \rangle$ (open circles). Whilethe DCF is the gr cross-correlation function, the $\langle DAF \rangle$ is the average of the gg and rr autocorrelation functions. We use the AE3g-AE3r events (see main text) and three bin semisizes: $\alpha =20$ ( top panel), 25 ( middle panel), and 30 ( bottom panel) d.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f9.eps}\end{figure}$ Figure 9: Normalised $\delta ^2$ function from the AE3g-AE3r events. We use bin semisizes $\alpha =20$ (dotted line), 25 (dashed line), and 30 (solid line) d. In Fig. 8, we can observe the presence of time shifts between the DCF and $\langle DAF \rangle$ , which translate into interband delay peaks centered on 3-4.5 d (AE3g leading AE3r).
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In the text

$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f1.eps}\end{figure}$	Figure 1: Observations of Q0957+561 with the Liverpool robotic telescope in the g band. We display system subframes ( left panels), model subframes ( middle panels), and residual subframes ( right panels) for five frames taken during the 2.5-year monitoring period (see main text).
Open with DEXTER

$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f2.eps}\end{figure}$	Figure 2: Colour coefficient in the g band. The values are distributed around the central discontinuous line (average coefficient), and most of them are placed between the top and bottom discontinuous lines (filled circles). Only seven extreme values (triangles and open circles) exceed these limits.
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$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f4.eps}\end{figure}$	Figure 4: Final magnitudes of Q0957+561A ( top panel) and Q0957+561B ( bottom panel) in the g band of the SDSS photometric system. These g-SDSS light curves include noticeable fluctuations covering a 2.5-year monitoring period from January 2005 to June 2007.
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$\begin{figure} \par\includegraphics[angle=0,width=7cm]{10447_f5.eps}\end{figure}$	Figure 5: Final magnitudes of Q0957+561A ( top panel) and Q0957+561B ( bottom panel) in the r band of the SDSS photometric system. The r-SDSS records from October 2005 to June 2007 (two whole seasons) incorporate different prominent features that are also seen in the g-SDSS curves (see Fig. 4), with the g-SDSS features having a larger amplitude.
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$\begin{figure} \par\includegraphics[angle=0,width=9cm]{10447_f8.eps}\end{figure}$	Figure 8: Comparison between the DCF (filled circles) and the $\langle DAF \rangle$ (open circles). Whilethe DCF is the gr cross-correlation function, the $\langle DAF \rangle$ is the average of the gg and rr autocorrelation functions. We use the AE3g-AE3r events (see main text) and three bin semisizes: $\alpha =20$ ( top panel), 25 ( middle panel), and 30 ( bottom panel) d.
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$\begin{figure} \par\includegraphics[angle=-90,width=7cm]{10447_f9.eps}\end{figure}$	Figure 9: Normalised $\delta ^2$ function from the AE3g-AE3r events. We use bin semisizes $\alpha =20$ (dotted line), 25 (dashed line), and 30 (solid line) d. In Fig. 8, we can observe the presence of time shifts between the DCF and $\langle DAF \rangle$ , which translate into interband delay peaks centered on 3-4.5 d (AE3g leading AE3r).
Open with DEXTER