MASTER-IAC: new dwarf nova outburst
ATel #7991; O. Gress, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), R. Rebolo, M. Serra-Ricart, N. Lodieu, G. Israelian (The Instituto de Astrofisica de Canarias), V. Kornilov, N. Tiurina, A. Kuznetsov, P. Balanutsa, I. Gorbunov, E. Popova (Lomonosov Moscow State University, Sternberg Astronomical Institute), D. Buckley, S. Potter, M. Kotze (South African Astronomical Observatory), N. M. Budnev, K. Ivanov (Applied Physics Institute, Irkutsk State University), A. Tlatov, D. Dormidontov, V. Senik, A. V. Parhomenko (Kislovodsk Solar Station of the Pulkovo Observatory), V. Krushinski, I. Zalozhnykh (Ural Federal University), Yu. Sergienko, A. Gabovich, V. Yurkov (Blagoveschensk Educational State University)
on 3 Sep 2015; 19:39 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Transient, Variables
MASTER OT J210140.49+215730.9 - new dwarf nova outburst, Ampl>4.5, no VIZIER source
MASTER-IAC auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 ) discovered OT source at (RA, Dec) = 21h 01m 40.49s +21d 57m 30.9s on 2015-09-03.03612 UT.
The OT unfiltered magnitude is 17.4m (limit 19.0m).
The OT is seen in 3 images. There is no minor planet at this place.
We have reference image without OT on 2015-07-23.99348 UT with unfiltered magnitude limit 19.2m in MASTER-IAC database, on 2015-08-10.8226UT with m_lim=19.5 in MASTER-Kislovodsk and about 200 reference images in full MASTER Net without OT up to 19.5. There is no any known source in VIZIER database inside 10"(up to 22m). So we can suggest the dwarf nove outburst with amplitude more then 4.5m.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/MASTEROTJ210140.49+215730.9.jpg
Spectral observations are required.
Current outbursts of known dwarf novae:
MASTER detects an outburst of CSS 091119:213938-023913 with unfiltered m_OT=14.3 on 2015-09-03 00:21:35.364UT and CSS080101 J232519-081819 with unfiltered m_OT=12.9 on 2015-08-27 00:50:25.046UT.
List of Optical Transients discovered by MASTER
MASTER Global Robotic Net