MASTER: bright PSN in IC2963 and dwarf novae outbursts

ATel #7732; V. Vladimirov (Lomonosov MSU), O. Gress (ISU), V. Lipunov (Lomonosov MSU), D. Buckley (SAAO), E. Gorbovskoy, V. Kornilov, A. Kuznetsov, P. Balanutsa, S. Antipin, N. Tiurina, V. Chazov, E. Popova, D. Vlasenko (Lomonosov Moscow State University, Sternberg Astronomical Institute),S. Potter, A. Kniazev, M. Kotze (The South African Astronomical Observatory), N. Budnev, K. Ivanov (Irkutsk State University), A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk solar station of the Pulkovo observatory RAS), V. Krushinsky, I. Zalozhnih (Ural Federal University)
on 30 Jun 2015; 07:32 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)

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MASTER OT J114925.48-050713.8 discovery - possible SuperNova (m=14.8) in IC2963

MASTER-SAAO auto-detection system ( Lipunov et al., Advances in Astronomy, MASTER Global Robotic Net, 2010 ) discovered OT source at (RA, Dec) = 11h 49m 25.48s -05d 07m 13.8s on 2015-06-29.77270 UT.
The OT unfiltered magnitude is 14.8m (limit 18.8m).
The OT is seen in 7 images. There is no minor planet at this place.

We have more then 150 reference imagew without OT in MASTER-Tunka, Kislovodsk, Amur and SAAO database, for ex., 2015-04-19.82909 UT with 18.2 unfiltered magnitude limit .

There is bright spiral IC2963 galaxy in 13.7"E and 7.6"S.

Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/114925.48-050713.8.png

MASTER183430.99-423155.9 discovery - dwarf nova in outburst with Ampl>4.5m

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 18h 34m 30.99s -42d 31m 55.9s on 2015-06-29.92524 UT.
The OT unfiltered magnitude is 17.3m (limit 18.4m).The OT is seen in 3 images. There is no minor planet at this place.
We have reference image without OT on 2015-05-03.98221 UT with 19.1 unfiltered magnitude limit.
There is only GSC 2.3.2 star with blue J=21.83, there is a very faint star on DSS images. So we can suggest dwarf nova in outburst with Ampl > 4.5m .
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/183430.99-423155.9.png

MASTER OT J182159.52-500108.1 discovery - possible CV in outburst

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 18h 21m 59.52s -50d 01m 08.1s on 2015-06-29.90931 UT.
The OT unfiltered magnitude is 17.2m (limit 18.2m).

The OT is seen in 3 images. There is no minor planet at this place.
We have reference image without OT on 2015-02-03.10382 UT with 18.4 unfiltered magnitude limit.
There is a faint star in red and blue on DSS images (with posible m<21), but it's known only as GSC2.3.2. star with red F=19.03 (1993y). So we can suggest a dwarf nova outburst with possible Ampl>3.8 (and previous burst in 1993).

Spectral observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/182159.52-500108.1.png

MASTER OT J074359.55-512302.2 discovery - dwarf nova in outburst with Ampl>5m

MASTER-SAAO auto-detection system discovered OT source at (RA, Dec) = 07h 43m 59.55s -51d 23m 02.2s on 2015-06-27.68897 UT. The OT unfiltered magnitude is 17.1m (limit 18.2m).
The OT is seen in 56 images. There is no minor planet at this place.
We have reference image without OT on 2014-12-25.00672 UT with 19.5 unfiltered magnitude limit.
There is a GSC 2.3.2 star with blue J=22.23. So we can suggest the dwarf nova outburst with Ampl>5m
Spectral observations are required.
The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/074359.55-512302.2.png

MASTER Global Robotic Net