New Eclipsing CV discovered by MASTER
ATel #6097; P. Balanutsa, D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, V. Kornilov, N. Shatskiy, V. Chazov, A. Kuznetsov, V. Vladimirov, V. Yecheistov (Moscow State University, SAI), K. Ivanov, S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress (Irkutsk State University), V. Yurkov, Y. Sergienko, D. Varda, E. Sinyakov, A. Gabovich (Blagoveshchensk Educational University), A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk Solar Station of Pulkovo Observatory), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov (Ural Federal University), P. Podvorotny, V. Shumkov, S. Shurpakov (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez, F. Podest (OAFA)
on 24 Apr 2014; 21:01 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Cataclysmic Variable, Transient, Variables
Referred to by ATel #: 6116
MASTER OT J192328.22+612413.5 - new Cataclysmic Variable
MASTER-Tunka auto-detection system discovered OT source at (RA, Dec) = 19h 23m 28.22s +61d 24m 13s.5s on 2014-04-20.82697 UT. The OT unfiltered magnitude is 17.5m (limit 19.3m). The OT is seen in 7 images. There is no minor planet at this place. We have reference image without OT on 2010-08-21.63309 UT with unfiltered magnitude limit 19.2m. The object was marginally visible (mag 19.1) on the first triplet of images obtained 1.1 hr before, on 2014-04-20.779 UT. It is also present on 2014-04-22.697 and 22.743 UT MASTER-Tunka images at 17.7m.
The OT at quiescence is identical to the blue star USNO-A2.0 1500-06848103 (19 23 28.36 +61 24 13.8 B=18.9 R=19.1) = USNO-B1.0 1514-0248617 (19 23 28.253 +61 24 13.25 pmRA=-12 pmDE=-16 B1=19.06 R1=19.86 B2=18.02 R2=20.10 I=18.15). Color-combined DSS finder chart is uploaded to http://master.sai.msu.ru/static/OT/J192328+612413-BRIR.jpg (10'x10' FOV). There is also an UV counterpart GALEX J192328.3+612413 (FUV=19.42+/-0.15 NUV=19.68+/-0.10). Finally, there is a faint ROSAT X-ray source 1RXS J192333.2+612507 (flux 0.0085+/-0.0029 cnt/s, hardness ratios HR1=-0.83+/-0.16 HR2=-0.08+/-1.35) formally 64" away, but with the error radius 14" and source extent 29". The object was also detected in the infrared as WISE J192328.25+612413.1 (W1=17.05+/-0.08 W2=17.33+/-0.31) and AllWISE J192328.25+612413.0 (W1=16.58+/-0.05 W2=16.60+/-0.14).
There is nothing at this position in 2MASS, GCVS and AAVSO VSX. Object is showing a large variability on the digitized Palomar plates and on NEAT images from 3 different nights. SDSS has missed the object by ~20". This area of sky in Draco is not covered by CRTS.
Based on the blue color, UV counterpart and fast variability, MASTER OT J192328.22+612413.5 is a new cataclysmic variable, likely an eclipsing polar. Follow up observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/192328.22612413.5.jpg
List of Optical Transients discovered by MASTER
Global MASTER Robotic Net