MASTER-SAAO: very bright dwarf nova outburst (Ampl>6.5m)
ATel #7513; P. Balanutsa, V. Lipunov (Lomonosov MSU), D. Buckley (SAAO), E. Gorbovskoy, S. Antipin, N. Tiurina, A. Kuznetsov, V. Kornilov, V. Chazov, V. Vladimirov (Lomonosov Moscow State University, Sternberg Astronomical Institute), O. Gress, N. Budnev, K. Ivanov, S. Yazev, V. Poleshchuk (Irkutsk State University), S. Potter, A. Kniazev, M. Kotze (The South African Astronomical Observatory), A. Tlatov, D. Dormidontov, V. Senik, A. Parkhomenko (Kislovodsk solar station of the Pulkovo observatory RAS), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov (Ural Federal University), Yu. Sergienko, V. Yurkov, A. Gabovich (Blagoveschensk State Educational University), V. Shumkov, S. Shurpakov (MASTER-Team)
on 15 May 2015; 23:50 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Transient, Variables
MASTER 175525.02-453916.8 discovery - new Dwarf Nova outburst with Ampl>6.5m
MASTER-SAAO auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 )
discovered OT source at (RA, Dec) = 17h 55m 25.02s -45d 39m 16.8s on 2015-05-13.888 UT. The OT unfiltered magnitude is 14.1m (the limit is 17.9m).
There are 3 images wuth OT. There is no minor planet at this place.
We have reference image without OT on 2015-02-03.11519 UT with 18.2 unfiltered magnitude limit.
MASTER OT isn't 0443-0655752 or 0443-0655775 USNO-B1 stars, it's between them, so the outburst came from the previousely unvisible star, and the Ampl. in this case is >6.5m
Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/175525.02-453916.8.png
MASTER Global Robotic Net