Period of the new CV MASTER OT J192328.22+612413.5
ATel #6116; P. Garnavich (Notre Dame), M. Kennedy (U. C. Cork)
on 4 May 2014; 23:48 UT
Credential Certification: Peter Garnavich (pgarnavi@gmail.com)
Subjects: Optical, Binary, Cataclysmic Variable, Variables
We obtained time-resolved photometry of the new
cataclysmic variable MASTER OT J192328.22+612413.5
(ATel #6097) with the Vatican Advanced Technology
Telescope (VATT) and VATT4K CCD camera. We observed
the star on four consecutive nights beginning 2014
April 29 (UT) with a typical cadence of 30 sec.
We witnessed two complete eclipses and parts of two
other eclipses confirming that the new CV is an
eclipsing system. The "V" shaped eclipses have
a depth of 3 magnitudes and last 30 minutes. From
the light curve features we find the orbital period of the
system is 4.024 +/-0.005 hours.
The first two nights the star had a SDSS-g magnitude
outside of eclipse between 19.5 and 19.2 mag calibrated
using nearby stars in the SDSS DR9 catalog. There was
a clear "hump" in the light curve starting an
hour before eclipse suggesting the presence of
an accretion hot spot on a disk. The last two
nights the star brightened to g=18 mag and the
pre-eclipse hump was absent.
We conclude that the new CV is not a polar as
suggested in the discovery ATel #6097. In general
it is similar to the active disk CV Lanning 386
(Brady et al. 2008, PASP, 120, 301) which has a
period of 3.94 hours, deep eclipses, a pre-eclipse
hump and frequent outbursts.
With thank Richard Boyle and the Vatican Observatory
for providing time on the VATT for these observations.
