MASTER: blue OT and dwarf nova outburst

ATel #8140; O. Gress, V. Lipunov, E. Gorbovskoy (Lomonosov MSU), D. Buckley (SAAO), V. Kornilov, N. Tiurina, A. Kuznetsov, P. Balanutsa, I. Gorbunov, D. Vlasenko, V. Chazov, E. Popova, V. Shumkov (M. V. Lomonosov MSU, SAI),S. Potter, M. Kotze (South African Astronomical Observatory), R. Rebolo, M. Serra-Ricart, N. Lodieu, G. Israelian (The Instituto de Astrofisica de Canarias), N. Budnev, K. Ivanov (Irkutsk State University, Applied Physics Institute), A. Tlatov, V. Senik, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Krushinskiy (Ural Federal University), Yu. Sergienko, A. Gabovich, V. Yurkov (Blagoveschensk Educational State University)
on 7 Oct 2015; 22:33 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

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MASTER OT J201211.65-564336.9 discovery - blue OT, Ampl>4m

MASTER-SAAO auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 ) discovered OT source at (RA, Dec) = 20h 12m 11.65s -56d 43m 36.9s on 2015-10-07.75574 UT.
The OT unfiltered magnitude is 18.4m (limit 20.2m).
The OT is seen at 10 images. There is no minor planet at this place. We have reference image without OT on 2015-05-15.10094 UT with unfiltered magnitude limit 20.0m.
There is a blue source in VIZIER database with jmag=21.22. There is no any source at this position at red POSS images, so we can suggest the amplitude of the burst is more then 4m (taking into account that possible Rmag_OT<22.5-23, and that MASTER unfiltered m=0.2B+0.8R)
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/201211.65-564336.9.png

MASTER OT J033608.39+435202.8 discovery - possible dwarf nova outburst, Ampl>2.4

MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) = 03h 36m 08.39s +43d 52m 02.8s on 2015-10-05.91288 UT.
The OT unfiltered magnitude is 17.1m (limit 19.6m).
The OT is seen in 6 images. There is no minor planet at this place. We have reference image with marginally seen OT (20.1) on 2011-10-27.98278 UT with 20.1 unfiltered magnitude limit.
Spectral observations are required.
There is a USNO B1 star with B2=20.49,R2=19.25, so we can suggest the dwarf nova outburst with unfiltered Ampl>2.4m

The discovery and reference images are available at: http://observ.pereplet.ru/images/MASTER033608.39+435202.8.png

MASTER Global Robotic Net