[vsnet-newvar 4445] MASTER OT J210316.39+314913.6 (fwd from ATel)

[Taichi Kato]

ATEL #6117							     ATEL #6117

Title:	New Bright CV discovered by MASTER
Author:	V. Shumkov, D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina,
		P. Balanutsa, V. Kornilov, N. Shatskiy, V. Chazov, A. Kuznetsov, V.
		Vladimirov, V. Yecheistov (Moscow State University, SAI), K. Ivanov,
		S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk,
		O. Gress (Irkutsk State University), V. Yurkov, Y. Sergienko, D. Varda,
		E. Sinyakov, A. Gabovich (Blagoveshchensk Educational University),
		A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk Solar
		Station of Pulkovo Observatory), V. Krushinsky, I. Zalozhnih, A. Popov,
		A. Bourdanov (Ural Federal University), P. Podvorotny, S. Shurpakov
		(MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci,
		C. Lopez, F. Podest (OAFA)
Queries:	lipunov2007 at gmail.com
Posted:	5 May 2014; 11:01 UT
Subjects:Optical, Cataclysmic Variable, Transient

MASTER OT J210316.39+314913.6 - new bright CV

MASTER-Tunka auto-detection system discovered OT source at (RA, Dec) =
21h 03m 16.39s +31d 49m 13.6s on 2014-05-03.84978 UT. The OT unfiltered
magnitude is 
13.9m
(limit 17.0m). The OT is seen in 11 images. There is no minor planet at
this place. We have reference image without OT on 2012-08-28.56197 UT with
unfiltered magnitude limit 18.6m. 

The OT at quiescence is identical to the blue star USNO-A2.0 1200-16918984
(21 03 16.46 +31 49 14.1 R=16.0 B=16.1) = USNO-B1.0 1218-0550734 (21 03
16.453 +31 49 13.98 pmRA=0 pmDE=0 B1=15.57 R1=15.57 B2=19.38 R2=N/A I=17.20).
Color-combined DSS finder chart is uploaded to http://master.sai.msu.ru/static/OT/J210316+314913-OVR.jpg
(10'x10' FOV). Object was in outburst on POSS-I blue and red plates taken
on 1953-06-15 and at quiescnce on four other DSS images. Comparison of
the 1st and 2nd epoch blue Palomar plates is uploaded to http://master.sai.msu.ru/static/OT/J210316+314913-POSS-B.jpg
(5'x5' FOV). 

There is nothing at this position in 2MASS, GCVS and AAVSO VSX. Galactic
latitude is -9.8 deg. This area of sky in Cygnus is not covered by SDSS,
NEAT and CRTS. 

Based on the blue color and outburst amplitude (~5m), MASTER OT J210316.39+314913.6
is a new cataclysmic variable (dwarf nova). Follow up observations are
required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/210316.39314913.6.png
(object was located within 60 pixels from the edge of 4kx4k CCD field of
view). 

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

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