MASTER-SAAO: bright outbursting OT
ATel #9004; V. Shumkov, V. Lipunov (Lomonosov MSU), D. Buckley (SAAO), V. Kornilov, E. Gorbovskoy, N. Tiurina, P. Balanutsa, O. Gress, A. Kuznetsov, D. Kuvshinov, V. Vladimirov, I. Gorbunov, D. Vlasenko, E. Popova (Lomonosov Moscow State University, SAI), S. Potter, A. Kniazev (The South African Astronomical Observatory), S. Shurpakov (MASTER-team)
on 28 Apr 2016; 06:26 UT
Credential Certification: Nataly Tyurina (firstname.lastname@example.org)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Transient, Variables
MASTER OT J212920.71-620852.2 discovery - fast outbursting possible dwarf nova with ampl>5.2m
MASTER-SAAO auto-detection system ( Lipunov et al., "MASTER Global Robotic Net",
Advances in Astronomy, 2010, 349171 ) discovered OT source at (RA, Dec) = 21h 29m 20.71s -62d 08m 52.2s on 2016-04-27.985 UT.
The OT unfiltered magnitude is 17.3m (the limit is 19.3m).
The OT became brighter on 2016-04-28 02:55:55.842 with unfiltered m_OT=16.8
There are 7 images with it.
We have reference image without OT on 2015-09-16.83396 UT with unfiltered magnitude limit 20.8m.
There is no known optical sources in VIZIER database (22m POSS limit), only ALLWISE source in 2.8" with W1,W2,W3,W4.
So the amplitude of current outburst is more then 5.2mag, and all these data points to classical dwarf nova outburst.
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/212920.71-620852.2.png
Outburst photometry (MASTER unfiltered W=0.2B+0.8R calibrated to USNO-B1):
2016-04-27 23:39:30.557 17.3
2016-04-27 23:51:23.241 17.3
2016-04-28 00:04:35.259 17.3
2016-04-28 02:52:22.246 16.8 (twin MASTER telecope)
2016-04-28 02:55:55.842 16.8 (twin MASTER telecope)
List of Optical Transients discovered by MASTER
MASTER Global Robotic Net