Robotic Monitoring of Gravitationally Lensed Quasars

Figure 4

LRT i-band light curves of FBQ 0951 + 2635 in February-May 2007. We compare the record of the A image (red circles) and the time- and magnitude-shifted light curve of the B image (green triangles; the noisy brightness record of B is shifted in time and magnitude, using the 16-day time delay of the system and an average magnitude difference of 1.094 mag). There is a reasonable agreement between both trends, and so we do not find evidence of short-timescale extrinsic variability.