MASTER: dwarf novae outbursts

ATel #10061; O. Gress, P. Balanutsa, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), S. Otero (AAVSO), R. Rebolo, M. Serra-Ricart (IAC), D. Buckley (SAAO), Tiurina N. V., Kuznetsov A. S., Kornilov V. G., Vladimirov V. V., Kuvshinov D. A., Chazov V. V., V. Shumkov, T. Pogrosheva (Lomonosov Moscow State University, SAI)
on 9 Feb 2017; 16:20 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

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MASTER OT J150518.03-143933.6 discovery - bright dwarf nova outburst, Ampl>4.4m

MASTER-IAC auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 15h 05m 18.03s -14d 39m 33.6s on 2017-02-08.27692 UT.
The OT unfiltered magnitude is 15.5m (limit 19.8m).
The OT is seen in 5 images. There is no minor planet at this place.
We have reference image with m_OT=19.9 on 2016-04-04.02185 UT with 19.9m unfiltered magnitude limit.
There is a GALEX source, i.e.accretion process, so the amplitude of current dwarf nova outburst is more then 4.4m.
Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/150518.03-143933.6.png

MASTER OT J191339.65-614257.6 discovery - dwarf nova outburst, Ampl>3.9m

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 19h 13m 39.65s -61d 42m 57.6s on 2017-02-08.10001 UT.
The OT unfiltered magnitude is 17.1m (mlim=19.1).
The OT is seen in 5 images. We have reference images without OT on 2015-05-25.94251 UT with unfiltered mlim= 21.0m, on 2016-08-05 18:00:08UT with mlim=19.6.
So, the ampltitude of current dwarf nova (there is a Galex source) outburst is more then 3.9m Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/191339.65-614257.6.png

MASTER OT J141301.33-674321.0 detection - long variable star

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 14h 13m 01.33s -67d 43m 21.0s on 2017-02-01.10981 UT.
The OT unfiltered magnitude is 12.0m (mlim=18.5).
The OT is seen in 11 images.
We have reference images with m_OT=14.8 on 2014-12-25 00:46:49.59UT, m_OT=13.5 on 2016-07-16 20:05:45.173UT.
There is USNO-B1 star with B2=15.86, R2=16.91, I=10.90, M8 star.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/141301.33-674321.0.png

MASTER Global Robotic Net