Spatially-correlated variables? Lensed quasar example

[drphilmarshall]

Hi! I'm interested in gravitationally-lensed quasars, which look like 2 or 4 variable point sources with highly time-correlated light curves that are offset from each other by a few arcsec on the sky and a few days to a few weeks in time. Here's a notebook showing some early multi-filter light curve analysis, and the example dataset we are looking at is this one. The data looks like this:

MJD   band  flux_A     flux_A_err     flux_B     flux_B_err     flux_C     flux_C_err     flux_D     flux_D_err 
59582.92000 u 3.24930 0.06473 2.97179 0.04874 3.99816 0.06473 2.04568 0.04874
59582.96000 g 3.48849 0.00333 4.04431 0.02381 3.20218 0.00333 2.67839 0.02381
59587.22000 u 4.07084 0.05930 3.77036 0.06234 2.82976 0.05930 3.64696 0.06234
59587.24000 u 6.57635 0.06558 2.68169 0.03230 3.49241 0.06558 3.47201 0.03230
59588.93000 g 4.17680 0.01984 2.91827 0.00995 4.14780 0.01984 3.41236 0.00995
59588.97000 g 3.39276 0.02039 3.02250 0.04673 5.78863 0.02039 4.06559 0.04673
59592.48000 r 4.24973 0.02077 4.53544 0.03213 3.30882 0.02077 3.05684 0.03213
59592.50000 i 5.06821 0.03161 4.21393 0.01450 3.63418 0.03161 3.10412 0.01450
59596.20000 y 5.46597 0.30899 4.07760 0.29980 4.44686 0.30899 4.00259 0.29980
59596.23000 z 4.67455 0.08453 3.95808 0.07931 4.42070 0.08453 3.82155 0.07931
...

I can dig out the sky positions of each image (A,B,C,D) if you're interested!