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New Cataclysmic Variable in Kepler field discovered by MASTER

ATel #6325; D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, P. Balanutsa, V. Kornilov, N. Shatskiy, V. Chazov, A. Kuznetsov, V. Vladimirov, 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 (Irkutsk State 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 18 Jul 2014; 21:15 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

Subjects: Optical, Cataclysmic Variable, Transient

Referred to by ATel #: 6584

MASTER OT J194955.17+455349.6 - new CV in Kepler field

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 19h 49m 55.17s +45d 53m 49.6s on 2014-07-18.55647 UT. The OT unfiltered magnitude is 16.4m (limit 17.6m). The OT is seen in 3 images. There is no minor planet at this place. We have reference image without OT on 2011-08-26.58258 UT with magnitude limit in R filter 18.6m.

The OT at quiescence is identical to the blue star USNO-B1.0 1358-0337295 (19 49 55.184 +45 53 51.21 pmRA=0 pmDE=0 B1=19.58 R1=18.93 B2=17.84 R2=19.08 I=17.31). The star is showing significant variability between Palomar plates. Vmag in GSC 2.3.2 is 17.55. Color-combined (BRIR) finder chart is uploaded to http://master.sai.msu.ru/static/OT/J194955+455349-BRIR5x5.jpg (2x zoom). There is a faint X-ray source 1RXS J194954.8+455347 with 12" error circle, flux 0.0284+/-0.0072 cnt/s and hardness ratios HR1=1.00+/-0.18, HR2=0.50+/-0.22 formally 5" away. There is nothing at this position in 2MASS, GCVS and AAVSO VSX. This area of sky in Cygnus is not covered by SDSS, GALEX, NEAT and CRTS.

The object is included into Kepler Input Catalog as KIC 9358280. The Kepler-INT survey (Greiss et al., 2012) gives the following magnitudes (rounded to 0.01): U=18.15 g=19.35 r=18.85 i=18.28 Ha=17.81 for KIS J194955.17+455350.9 and U=18.71 g=19.70 r=19.13 i=18.57 Ha=17.92 for KIS J194955.19+455350.9 (the same object observed at different epochs). Based on the H-alpha emission, MASTER OT J194955.17+455349.6 is a new cataclysmic variable, likely a dwarf nova in outburst. Follow up observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/194955.17455349.6.jpg

We note that MASTER OT J193347.47+442455.5 (ATel #6317), MASTER OT J185510.67+434138.0 = KIC 7873220 (ATel #6228) and MASTER OT J185624.15+400311.8 (ATel #6187) are also located in Kepler field.

List of Optical Transients discovered by MASTER

Global MASTER Robotic Net