New bright CV with large outburst amplitude discovered by MASTER
ATel #5196; S. Shurpakov, D. Denisenko, V. Lipunov, E. Gorbovskoy, P. Balanutsa, N. Tiurina, V. Kornilov, N. Shatskiy, V. Chazov, A. Kuznetsov, V. Yecheistov (Moscow State University, SAI), V. Yurkov, Y. Sergienko, D. Varda, E. Sinyakov, A. Gabovich (Blagoveshchensk Educational University), K. Ivanov, S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress, A. Frolova (Irkutsk State University), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov (Ural Federal University), A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk solar station of the Pulkovo observatory RAS), P. Podvorotny, V. Shumkov (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez and F. Podest (OAFA)
on 5 Jul 2013; 21:11 UT
Credential Certification: Vladimir Lipunov (lipunov2007@gmail.com)
Subjects: Optical, Cataclysmic Variable, Transient
MASTER OT J181953.76+361356.5 - new bright CV with 7m outburst amplitude
MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 18h 19m 53.76s +36d 13m 56.5s on 2013-07-05.65833 UT. The OT unfiltered magnitude is 14.0m (limit 18.0m). The OT is seen in 2 images. There is no minor planet at this place. We have reference image without OT on 2012-08-08.61723 UT with unfiltered magnitude limit 19.2m.
There is a faint star at this position on Palomar blue plates. It is present in GSC 2.3.2 with the coordinates 18 19 53.798 +36 13 56.15 and jmag=21.58. Color-combined (BRIR) DSS finder chart is uploaded to http://master.sai.msu.ru/static/OT/J181953+361356-BRIR5x5.jpg
The object has an UV counterpart GALEX J181953.9+361358 (FUV=22.39+/-0.27 NUV=21.76+/-0.19). There is nothing at this position in 1RXS, USNO-B, 2MASS, GCVS and AAVSO VSX. This area of sky in Lyra is not covered by SDSS. No previous outbursts were detected by Catalina Sky Survey, as well as on 12 images obtained by NEAT project on 4 different nights in 1998-1999.
Based on the blue color and outburst amplitude (more than 7m) we conclude that MASTER OT J181953.76+361356.5 is a new cataclysmic variable, most likely of UGWZ (WZ Sge) subtype. Follow up observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/181953.76361356.5.png
List of Optical Transients discovered by MASTER
Global MASTER Robotic Net
