MASTER-IAC, MASTER-SAAO: 2 bright OTs

ATel #9078; O. Gress (ISU), T. Pogrosheva, V. Lipunov (Lomonosov MSU), R. Rebolo Lopez (IAC), D. Buckley (SAAO), E. Gorbovskoy, N. Tiurina, P. Balanutsa, I. Gorbunov, A. Kuznetsov, E. Popova, D. Kuvshinov (Lomonosov MSU, SAI), M. Serra-Ricart, G. Israelian (IAC), S. Potter, A. Kniazev (SAAO)
on 24 May 2016; 22:32 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

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MASTER OT J001021.33+731516.5 discovery - possible dwarf nova outburst, Ampl>4m

MASTER-IAC auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 349171 ) discovered OT source at (RA, Dec) = 00h 10m 21.33s +73d 15m 16.5s on 2016-05-24.18141 UT.
The OT unfiltered magnitude is 15.7m (limit 18.1m).
The OT is seen in 4 images. There is no minor planet at this place.
We have the following reference images without OT
Date(UT), m_lim(unfiltered), MASTER observatory
2015-08-18.87785 m_lim 19.3m (MASTER-IAC database),
2015-01-15 16:45:51UT m_lim=19.6 (MASTER-Kislovodsk),
2014-10-03 19:04:16UT m_lim=19.6 (MASTER-Kislovodsk),
2012-09-08 17:30:52UT m_lim=19.2 (MASTER-Tunka)
2011-12-26 11:44:57UT m_lim=19.0 (MASTER-Tunka)
2010-10-09 12:08:50UT m_lim=19.4 (MASTER-Tunka)

. There is USNO-B1 star with B1=20.24, R1=19.49 (one of last outbursts), so we suggest the amplitude of current outburst is more then 4m
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/001021.33731516.5.png

MASTER OT J203111.28-625350.6 discovery - possible dwarf nova, Ampl>5.3m

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 20h 31m 11.28s -62d 53m 50.6s on 2016-05-16.85579 UT.
The OT unfiltered magnitude is 16.7m (limit 18.5m). The OT is seen in 2 images. There is no minor planet at this place.
We have reference image without OT on 2015-10-10.77578 UT with unfiltered magnitude limit 20.2m.
There is GALEX source in 2.8". so the amplitude of current outburst is more then 5.3(POSS 22m limit)

Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/203111.28-625350.6.png

Current outbursts, detected by MASTER software:
MASTER OT J180606.58+272108.8 (ASASSN-13ct) on 2016-05-24 02:21:39.752 with unfiltered m_OT=15.8
and
MASTER OT J223854.45+053607.5 (SDSSJ223854.51+053606.8) on 2016-05-23 03:40:23.608UT with unfiltered m_OT=15.8

MASTER Global Robotic Net