Gravitationally lensed quasars offer a unique opportunity to study
cosmological and extragalactic phenomena, using reliable light curves of the
lensed images. This requires accurate deblending of the quasar images, which is
not trivial due to the small separation between the lensed images (typically
$\sim1$ arcsec) and because there is light contamination by the lensing galaxy
and the quasar host galaxy. We propose a series of experiments aimed at testing
our ability to extract precise and accurate photometry of lensed quasars. In
this first paper, we focus on evaluating our ability to extract light curves
from simulated CCD images of lensed quasars spanning a broad range of
configurations and assuming different observational/instrumental conditions.
Specifically, the experiment proposes to go from pixels to light curves and to
evaluate the limits of current photometric algorithms. Our experiment has
several steps, from data with known point spread function (PSF), to an unknown
spatially-variable PSF field that the user has to take into account. This paper
is the release of our simulated images. Anyone can extract the light curves and
submit their results by the deadline. These will be evaluated with the metrics
described below. Our set of simulations will be public and it is meant to be a
benchmark for time-domain surveys like Rubin-LSST or other follow-up
time-domain observations at higher temporal cadence. It is also meant to be a
test set to help develop new algorithms in the future.

Cet article explore les excursions dans le temps et leurs implications.

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