Аннотация: MASTER OT J184121.42+341646.7 discovery - new OT, dwarf nova outburst? Ampl>5m,no sources in VIZIER
MASTER-IAC auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L ) discovered OT source at (RA, Dec) = 18h 41m 21.42s +34d 16m 46.7s on 2017-01-26.25294 UT.
The OT unfiltered magnitude is 17.0m (limit 18.9m).
The OT is seen in 5 images. There is no minor planet at this place.
We have reference image without OT on 2016-07-10.07728 UT with unfiltered magnitude limit 20.3m. There is no any known sources in VIZIER database, so 22mag POSS limit gives more then 5m of current outburst's amplitude
Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/184121.42341646.7.png
MASTER OT J020404.19+741804.6 discovery
MASTER-IAC auto-detection system discovered OT source at (RA, Dec) = 02h 04m 04.19s +74d 18m 04.6s on 2017-01-26.08373 UT.
The OT unfiltered magnitude is 16.8m (limit 19.6m).
The OT is seen in 8 images, plus its previous outbursts are presented in MASTER-IAC database on 2015-11-02 03:52:29.478 with m_OT=16.4, on 2016-01-23 00:35:29.523 with m_OT=17.1.
We have reference image without OT on 2015-11-05.03773 UT with unfiltered magnitude limit 19.8m. So current outburst's Ampl is more then 3m.
There is USNO B1 star with previous outbursts with B1=20.97,R1=18.94 (There is no known variable stars in AAVSO database(VSX) within 1' of 02 04 04.20 +74 18 04.6.)
Spectral observations are required.
The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/020404.19741804.6.png