MASTER-IAC: 3 possible dwarf nova outburst
ATel #8013; O. Gress, V. Vladimirov, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), R. Rebolo, M. Serra-Ricart, N. Lodieu, G. Israelian (The Instituto de Astrofisica de Canarias),V. Kornilov, P. Balanutsa, N. Tiurina, A. Kuznetsov, I. Gorbunov, V. Chazov, D. Vlasenko (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 (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 7 Sep 2015; 23:31 UT
Credential Certification: Nataly Tyurina (firstname.lastname@example.org)
Subjects: Optical, Request for Observations, Cataclysmic Variable, Transient, Variables
MASTER OT J220633.99+312137.0 discovery - new bright dwarf nova outburst, Ampl>5.5 (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) = 22h 06m 33.99s +31d 21m 37.0s on 2015-09-07.0329 UT.
The OT unfiltered magnitude is 16.5m (the limit is 20.2m).
There are 3 images with OT. There is no minor planet at this place. There is no any source inside 5" in VIZIER. We have more then 100 reference images without OT in MASTER-Kislovodsk, MASTER-Tunka and MASTER-Amur database(for ex.on 2014-11-23.646UT, m_lim=20.1) from 2010-07-28. So we can suggest the dwarf nova outburst with amplitude more then 5.5
Spectral observations are required.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/MASTER220633.99+312137.0.jpg
MASTER OT J225632.47+354238.1 detection - dwarf nova outburst, ampl > 3.5m
MASTER-IAC auto-detection system discovered OT source at (RA, Dec) = 22h 56m 32.47s +35d 42m 38.1s on 2015-09-07.0706 UT.
The OT unfiltered magnitude is 16.9m (limit 19.7m).
There are 3 images with OT. There is no minor planet at this place. We have reference images without OT on 2015-07-28 21:26:13 with unfiltered m_lim=18.8, on 2012-09-16.0859UT with m_lim=19.9, on 2013-07-11.906UT with m_lim=19.3 in MASTER-Kislovodsk database; on 2014-08-26.662UT with m_lim=20.2, 2010-11-13.5597UT with m_lim=19.8 (MASTER-Tunka), on 2014-09-21.528UT with m_lim=19.3(MASTER-Amur).
There is GSC2.3 star with red 20.26 and blue 21.12m.
So we can suggest the dwarf nova outburst with ampl > 3.5m
The discovery and reference images are available at http://observ.pereplet.ru/images/MASTEROTJ225632.47+354238.1.jpg
MASTER OT J223633.20+374621.1 detection - dwarf nova outburst, Ampl>3.3
MASTER-IAC auto-detection system discovered OT source at (RA, Dec) = 22h 36m 33.20s +37d 46m 21.1s on 2015-09-07.05106 UT.
The OT unfiltered magnitude is 16.5m (the limit is 19.7m). There are 4 images with this OT.
There is previous outburst on 2011-11-29.526UT with m_OT=19.9 in MASTER-Tunka database. There are about 100 images in MASTER-Tunka and -Kislovodsk with m_lim up to 19.6 from 2011-09-28.760 (for ex.,on 2015-07-24.99602 UT with 19.2 unfiltered magnitude limit).
There is USNO B1 star with B1/B2=20.76/20.46, R1/R2=19.57/19.66.So we can suggest the dwarf nova outburst with amplitude more then 3.3m.
The discovery and reference images are available at http://observ.pereplet.ru/images/MASTEROTJ223633.20+374621.1.jpg
List of Optical Transients discovered by MASTER
MASTER Global Robotic Net