[vsnet-alert 18892] MASTER OT J111724.72-200029.2

[Taichi Kato]

   Good candidate for a WZ Sge-type object.  Please observe!

===

ATEL #7847                                                           ATEL #7847

Title:  MASTER-SAAO: very bright optical transient
Author: V. Vladimirov, V. Lipunov, E. Gorbovskoy (Lomonosov MSU),
                D. Buckley (SAAO), P. Balanutsa, A. Kuznetsov, N. Tiurina, V. Kornilov,
                D. Vlasenko, I. Gorbunov, V. Chazov  (Lomonosov Moscow State University,
                Sternberg Astronomical Institute), S. Potter, M. Kotze (South African
                Astronomical Observatory), R. Rebolo, M. Serra-Ricart , N. Lodieu,
                G. Israelian (The Instituto de Astrofisica de Canarias), O. Gress,
                N. M. Budnev, K. Ivanov (Applied Physics Institute, Irkutsk State
                University), A. Tlatov, D. Dormidontov, V. Senik, A. V. Parhomenko
                (Kislovodsk Solar Station of the Pulkovo Observatory), V. Krushinski,
                I. Zalozhnykh (Ural Federal University), Yu. Sergienko, A. Gabovich,
                V. Yurkov (Blagoveschensk Educational State University)
Queries:        tiurina at sai.msu.ru
Posted: 27 Jul 2015; 21:27 UT
Subjects:Optical, Request for Observations, Cataclysmic Variable,
                Nova, Transient

MASTER OT J111724.72-200029.2 discovery - possible Nova with Amplitude
more then 7.3m (no any VIZIER source)

MASTER-SAAO auto-detection system  (  <A HREF="http://www.hindawi.com/journals/aa/2010/34917
1/">Lipunov
et al., Advances in Astronomy, MASTER Global Robotic Net, 2010</A> ) 
discovered OT source at (RA, Dec) = 11h 17m 24.72s -20d 00m 29.2s on 2015-07-25.74441
UT. 

The OT unfiltered magnitude is 
14.7m
(the limit is 18.8m). There are 3 images with OT on 2015-07-25 (25.74996,
25.75532 UT). 

There are 4 images with 
m=15.3
on 2015-07-27.72022, 27.732. We have reference images without OT on 2015-01-21.90010
UT with 20.2 unfiltered magnitude limit. 

There is no minor planet at this place. There is no any source in VIZIER
database inside 10". So we can suggest the Nova outburst with amplitude
more then 7.3m or possible dwarf nova outburst. 

Spectral observations are required. 

The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/1117
24.72-200029.2.png

<center><a href="http://observ.pereplet.ru/MASTER_OT.html">List of Optical
Transients discovered by MASTER</a></center> 

MASTER Global Robotic Net: http://observ.pereplet.ru