MASTER: 2 bright dwarf novae outbursts

ATel #8221; P. Balanutsa, O. Gress, V. Lipunov (M. V.Lomonosov), D. Buckley (SAAO), V. Kornilov, N. Tiurina, A. Kuznetsov, E. Popova, V. Vladimirov, I. Gorbunov, D. Vlasenko, V. Chazov(M. V.Lomonosov Moscow State University, Sternberg AStronomical Institute), S. Potter, A. Knyazev, M. Kotze (South African Astronomical Observatory)
on 29 Oct 2015; 12:10 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

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MASTER OT J070435.24-403441.1 discovery - dwarf nova outburst with Amplitude > 6.2m

MASTER-SAAO auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 ) discovered OT source at (RA, Dec) = 07h 04m 35.24s -40d 34m 41.1s on 2015-10-28.99737 UT.
The OT unfiltered magnitude is 15.8m (limit 18.4m).
The OT is seen in 3 images with constant m_OT=15.8m. There is no minor planet at this place.
We have reference image without OT on 2015-02-18.89542 UT with unfiltered magnitude limit 20.4m.
There is no an source inside 5" in VIZIER database(and POSS images, it means, there is no sources up to 22m). So we tell about dwarf nova outburst with Amplitude more then 6.2mag.
Spectral observations are required.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/070435.24-403441.1.png

MASTER OT J101545.73-675357.5 discovery - dwarf nova outburst with Amplitude > 6.4m

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 10h 15m 45.73s -67d 53m 57.5s on 2015-10-28.03846 UT.
The OT unfiltered magnitude is 14.9m (limit 17.9m).
The OT is seen in 4 images. There is no minor planet at this place.We have reference image without OT on 2015-02-25.94848 UT with unfiltered magnitude limit 21.2m.
So we suggest dwarf nova outburst with amplitude more then 6.4mag (There is a star with variable B,R in USNO,GSC,etc.)
Spectral observations are required.
The discovery and reference images are available at http://master.sai.msu.ru/static/OT/101545.73-675357.5.png

MASTER Global Robotic Net