Three OTs discovered by MASTER

ATel #4150; P. Balanutsa, D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, V. Kornilov, A. Belinski, N. Shatskiy, V. Chazov, A. Kuznetsov, D. Zimnukhov, D. Gareeva (Moscow State University, SAI) V. Krushinsky, I. Zalozhnih, A. Popov (Ural State 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 the Pulkovo observatory RAS) V. Yurkov, Y. Sergienko, D. Varda, E. Sinyakov (Blagoveshchensk Educational University) P. Podvorotniy, V. Shumkov, S. Shurpakov (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez and F. Podest (Observatorio Astronomico Felix Aguilar; OAFA)
on 5 Jun 2012; 13:45 UT
Credential Certification: Vladimir Lipunov (lipunov2007@gmail.com)

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MASTER J221621.91+705415.5 - new CV

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 22h 16m 21.91s +70d 54m 15.5s on 2012-06-03.65575 UT. The OT unfiltered magnitude is 15.3m (limit 17.3m). The OT is seen in 2 images. We have reference image without OT on 2011-11-23.39090 UT with magnitude limit in 'R' filter 18.4m.

This star was in outburst on the 1st epoch Palomar plates taken on 1952-08-19 and in quiescence on other DSS plates. It is present in USNO-A2.0 catalog with R=16.5, B=16.9 and in USNO-B1.0 as USNO-B1.0 1609-0150654 (RA=22 16 21.796 Dec=+70 54 16.04 B1=17.43 R1=16.54 B2=20.36 R2=19.53). The animation of two POSS Blue plates from 1952 and 1992 is available at http://master.sai.msu.ru/static/OT/J221621+705415-anim-DSS.gif

The object was also in outburst on 2MASS images obtained on 2000-06-21. It is present in 2MASS catalogue as 2MASS 22162188+7054156 (J=15.287 H=15.205 K=15.084).

This OT is identical to the star SDSS J221621.92+705416.1 (g=20.57 r=20.23 i=19.99). It is not present in GCVS and in AAVSO VSX. Based on the blue colors, detection of the previous outbursts and amplitude of variability we conclude that MASTER J221621.91+705415.5 is a new cataclysmic variable (dwarf nova).
Follow up observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/221621.91705415.5_1.png

MASTER J221811.12+654219.9 - new bright CV

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 22h 18m 11.12s +65d 42m 19.9s on 2012-06-03.65463 UT. The OT unfiltered magnitude is 14.3m (limit 17.3m). The OT is seen in 2 images.

We have reference image without OT on 2011-08-26.62979 UT with magnitude limit in 'R' filter 18.7m.
This object is identical to the star USNO-B1.0 1557-0236778 (RA=22 18 10.965 Dec=+65 42 20.22 B1=20.52 R1=19.14 B2=19.87 R2=19.28 I=18.56).
No previous outbursts were found on DSS plates. Nothing is present at this position in GCVS, 1RXS and 2MASS catalogues and in AAVSO VSX.
This area is not covered by SDSS and GALEX. Based on the amplitude of variability we suggest that MASTER J221811.12+654219.9 is a new cataclysmic variable in outburst.
Follow up observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/221811.12654219.9_1.png

MASTER J220943.06+653834.1 - ?

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 22h 09m 43.06s +65d 38m 34.1s on 2012-06-03.65463 UT. The OT unfiltered magnitude is 17.5m (limit 17.6m). The OT is seen in 2 images. We have reference image without OT on 2011-08-26.66396 UT with magnitude limit in 'R' filter 19.1m.

No previous outbursts were found on DSS plates. Nothing is present at this position in GCVS, 1RXS and 2MASS catalogues and in AAVSO VSX. This area is not covered by SDSS and GALEX. Spectral observations are required to determine the nature of this OT.

The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/220943.06653834.1_2.png

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