MASTER: 3 optical transients

ATel #8624; P. Balanutsa, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), D. Buckley(SAAO), N. Tiurina, V. Kornilov, O. Gress, A. Kuznetsov, V. Shumkov, V. Vladimirov, I. Gorbunov, D. Vlasenko(Lomonosov Moscow State University, Sternberg Astronomical Institute), S. Potter, M. Kotze (The South African Astronomical Observatory), A. Tlatov, V. Senik, D. Dormidontov, A. Parkhomenko(Kislovodsk Solar Station, Main Pulkovo observatory)
on 1 Feb 2016; 23:20 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

Tweet

MASTER OT J063329.26+385509.2 discovery - dwarf nova outburst, Ampl>4.3 m(no known data in VIZIER)

MASTER-Kislovodsk auto-detection system ( Lipunov et al., 2010 ) discovered OT source at (RA, Dec) = 06h 33m 29.26s +38d 55m 09.2s on 2016-01-30.80899 UT.
The OT unfiltered magnitude is 17.3m (the limit is 19.9m).
The OT is seen in 6 images. We have reference image without OT on 2012-11-17.87139 UT with unfiltered magnitude limit 19.6m. We have observed this coordinates several hundreds times since 2009(MASTER-Amur) and 2010 (-Tunka -Kislovodsk without OT up to 20.5.
There is no known source in VIZIER database, it means the POSS limit to this source in 22m.
Spectral observations are required.
The discovery and reference images are available at http://observ.pereplet.ru/images/MASTER063329.26+385509.2.jpg

MASTER OT J190956.59+383535.7 discovery - dwarf nova outburst, Ampl>5m

MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) = 19h 09m 56.59s +38d 35m 35.7s on 2016-01-31.07325 UT.
The OT unfiltered magnitude is 17.6m (limit 18.5m).
The OT is seen in 3 images. We have reference image without OT on 2014-05-04.93269 UT with unfiltered magnitude limit 19.1m.
There is only 2 Sloan stars known befor: the red one and the typical candidate to dwarf nova.
Spectral observations are required.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/190956.59383535.7.png

MASTER OT J072119.13-531755.3 discovery - possible dwarf nova outburst, Ampl>3.6m, no VIZIER

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 07h 21m 19.13s -53d 17m 55.3s on 2016-01-28.95079 UT.
The OT unfiltered magnitude is 18.4m (limit 19.3m).
The OT is seen in 3 images. There is no minor planet at this place.
We have reference image without OT on 2015-02-23.85772 UT with unfiltered magnitude limit 20.6m.
Spectral observations are required.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/072119.13-531755.3.png

MASTER Global Robotic Net