[vsnet-alert 14426] (fwd) MASTER OT J174305.70+231107.8

[Taichi Kato]

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The Astronomer's Telegram                   http://www.astronomerstelegram.org

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ATEL #4022							     ATEL #4022

Title:	Detection of the  MASTER OT J174305.70+231107.8
Author:	 P. Balanutsa, D. Denisenko, V. Lipunov, V. Shumkov, E. Gorbovskoy,
		N. Tiurina, V. Kornilov, A. Belinski, N. Shatskiy, V. Chazov, A. Kuznetsov,
		D. Zimnukhov (Moscow State University, SAI) V. Krushinsky, I. Zalozhnih,
		A. Popov (Ural Federal University) K. Ivanov, S. Yazev, N. Budnev,
		E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress (Irkutsk State
		University) A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk
		solar station of the Pulkovo observatory RAS) V. Yurkov, Y. Sergienko,
		D. Varda, E. Sinyakov (Blagoveshchensk Educational University), S.
		Shurpakov, P. Podvorotniy  (MASTER team members), Hugo Levato and
		Carlos Saffe (Instituto de Ciencias Astronomicas, de la Tierra y del
		Espacio; ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest
		(Observatorio Astronomico Felix Aguilar; OAFA)
Queries:	lipunov2007 at gmail.com
Posted:	9 Apr 2012; 16:37 UT
Subjects:Optical, Cataclysmic Variable, Transient


MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 17h
43m 05.70s +23d 11m 07.8s on 2012-04-05.83111 UT. 
The OT unfiltered magnitude is 15.6m (limit 17.5m). 
The OT is seen in 2 images. There is no minor planet at this place. 
We have reference image without OT on 2010-05-15 23:54:39 UT with unfiltered
magnitude limit 20.2m (MASTER-Kislovodsk site). 

There is a blue star in USNO catalog at the position of MASTER OT 
J174305.70+231107.8 which was brighter on the 1st epoch Palomar images

taken on 1951 June 27: 
USNO-B1.0 1131-0296601 
17 43 05.747 +23 11 08.36  pmRA=0  pmDE=0 B1=19.30 R1=18.55 B2=20.21 
R2=20.09 I=N/A 

We have found four previous outbursts of this CV in the publicly 
available survey data. 
<A HREF="http://skys.gsfc.nasa.gov/skymorph/skymorph.html">Palomar/NEAT</A>:
2003 July 28 (16.2m) fading to 17.1m by 2003 Aug. 07; 
2005 July 26 (17.5m). 
<A HREF="http://nesssi.cacr.caltech.edu/DataRelease/">CRTS</A>: 2007 May
15 (16.1m) and 2008 Apr. 08 (16.6m). 

Reported magnitudes are unfiltered with the Red (USNO-B1.0) zero point.

The object is not present in AAVSO VSX, 2MASS, 1RXS and catalogs. Its position
is 
not covered by SDSS and GALEX.  

Based on the blue color, outburst amplitude and archival light curve 
we conclude that MASTER OT J174305.70+231107.8 is a new cataclysmic variable

(dwarf nova) in outburst. Photometric time series are encouraged. 

The discovery and reference images are available at: 
http://observ.pereplet.ru/images/MASTER120753.01+455635/MASTER120753.01+455635.jpg

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