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New CV and Active Quasar detected by MASTER

ATel #6031; O. Gress (Irkutsk State University), 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 (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 31 Mar 2014; 17:46 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

Subjects: Optical, Cataclysmic Variable, Quasar, Transient

MASTER OT J151902.07+823951.2 - new CV

MASTER-Tunka auto-detection system discovered OT source at (RA, Dec) = 15h 19m 02.07s +82d 39m 51.2s on 2014-03-30.64057 UT. The OT unfiltered magnitude is 17.3m (limit 19.4m). The OT is seen in 6 images. There is no minor planet at this place. We have reference image without OT on 2011-12-18.97449 UT with unfiltered magnitude limit 19.5m.

There is nothing at this position on the digitized Palomar plates and on their combination to the limiting magnitude ~22.5. Color-combined (3xBRIR) finder chart is uploaded to http://master.sai.msu.ru/static/OT/J151902+823951-BRIR5x5.jpg (2x zoom). However, there is an UV counterpart GALEX J151901.9+823951 (FUV=19.58+/-0.11 NUV=19.48+/-0.07). Object is not present in 1RXS, 2MASS, USNO, GCVS and AAVSO VSX. This area of sky in Ursa Minor is not covered by SDSS and CRTS.

Based on the outburst amplitude (at least 5m) and UV detection, MASTER OT J151902.07+823951.2 is a new cataclysmic variable, most likely a dwarf nova of SU UMa (UGSU) type in superoutburst. Follow up observations are encouraged. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/151902.07823951.2.png

MASTER OT J140552.41+634223.5 - new active quasar

MASTER-Tunka auto-detection system discovered OT source at (RA, Dec) = 11h 55m 23.94s +33d 55m 37.3s on 2014-03-30.70826 UT. The OT unfiltered magnitude is 18.3m (limit 19.3m). The OT is seen in 4 images. There is no minor planet at this place. We have reference image without OT on 2011-05-23.69462 UT with unfiltered magnitude limit 19.5m.

The OT at quiescence is identical to the star-like object USNO-B1.0 1239-0201777 (11 55 23.847 +33 55 37.82 B1=19.79 R1=N/A B2=19.27 R2=19.63 I=18.78) = SDSS J115523.85+335537.4 (g=19.66 r=19.62 i=19.46) with unknown redshift. It has an infrared counterpart WISE J115523.85+335537.7 (W1=16.58 W2=14.89 W3=11.70 W4=8.82). Light curve from Catalina Sky Survey shows the brightening trend from the average level 19.5 to 18.8m in 2009-2013: CSS J115523.8+335537.

Object is listed in Photometric Classification Catalogue of SDSS DR7 (Abraham et al., 2012) with a 100% probability of being a low redshift Quasar and 0% that of star. Based on the slow variability, UV and IR detection, MASTER OT J140552.41+634223.5 is likely an active quasar. Multiwavelength follow up observations are required. Discovery and reference images are available at: http://master.sai.msu.ru/static/OT/115523.94335537.3.png

List of Optical Transients discovered by MASTER

Global MASTER Robotic Net