  On 26 September 2022, the Double Asteroid Redirection Test (DART) spacecraft
impacted Dimorphos, the satellite of binary near-Earth asteroid (65803)
Didymos. This demonstrated the efficacy of a kinetic impactor for planetary
defense by changing the orbital period of Dimorphos by 33 minutes (Thomas et
al. 2023). Measuring the period change relied heavily on a coordinated campaign
of lightcurve photometry designed to detect mutual events (occultations and
eclipses) as a direct probe of the satellite's orbital period. A total of 28
telescopes contributed 224 individual lightcurves during the impact apparition
from July 2022 to February 2023. We focus here on decomposable lightcurves,
i.e. those from which mutual events could be extracted. We describe our process
of lightcurve decomposition and use that to release the full data set for
future analysis. We leverage these data to place constraints on the post-impact
evolution of ejecta. The measured depths of mutual events relative to models
showed that the ejecta became optically thin within the first ~1 day after
impact, and then faded with a decay time of about 25 days. The bulk magnitude
of the system showed that ejecta no longer contributed measurable brightness
enhancement after about 20 days post-impact. This bulk photometric behavior was
not well represented by an HG photometric model. An HG1G2 model did fit the
data well across a wide range of phase angles. Lastly, we note the presence of
an ejecta tail through at least March 2023. Its persistence implied ongoing
escape of ejecta from the system many months after DART impact.
