Variable Stars in the giant satellite galaxy Antlia 2
  We report 350 pulsating variable stars found in four DECam fields ($\sim 12$
sq. deg.) covering the Antlia 2 satellite galaxy. The sample of variables
includes 318 RR Lyrae stars and eight anomalous Cepheids in the galaxy.
Reclassification of several objects designated previously to be RR Lyrae as
Anomalous Cepheids gets rid of the satellite's stars intervening along the line
of sight. This in turn removes the need for prolific tidal disruption of the
dwarf, in agreement with the recently updated proper motion and peri-centre
measurements based on Gaia EDR3. There are also several bright foreground RR
Lyrae stars in the field, and two distant background variables located $\sim
45$ kpc behind Antlia 2. We found RR Lyrae stars over the full search area,
suggesting that the galaxy is very large and likely extends beyond our observed
area. The mean period of the RRab in Antlia 2 is 0.599 days, while the RRc have
a mean period of 0.368 days, indicating the galaxy is an
Oosterhoff-intermediate system. The distance to Antlia 2 based on the RR Lyrae
stars is $124.1$ kpc ($\mu_0=20.47$) with a dispersion of $5.4$ kpc. We
measured a clear distance gradient along the semi-major axis of the galaxy,
with the South-East side of Antlia 2 being $\sim13$ kpc farther away from the
North-West side. This elongation along the line of sight is likely due to the
ongoing tidal disruption of Ant 2.
