[vsnet-alert 14875] New Bright CV in Hercules by MASTER

[Denis Denisenko]

Dear all,

I have discovered yet another bright dwarf nova in Hercules from
MASTER-Amur images with two previous outbursts in NEAT data. The
discovery was just announced by MASTER Team in ATel 4324 (D.
Denisenko, V. Lipunov, N. Tiurina et al.), see
<http://www.astronomerstelegram.org/?read=4324>. Outburst is "hot",
the latest image with the star in quiescence was obtained just 2 days
ago, on Aug. 19. Outburst amplitude is about 5m, so this one may be a
new SU UMa-type variable. Photometry is encouraged!

I am forwarding the text of the Telegram below.

Denis Denisenko

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The Astronomer's Telegram #4324
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Posted on 21 Aug 2012; 15:24 UT

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New Bright CV in Hercules discovered by MASTER
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MASTER OT J174902.10+191331.2 - new bright CV

MASTER-Amur auto-detection system discovered OT source at (RA, Dec) =
17h 49m 02.10s +19d 13m 31.2s on 2012-08-21.51684 UT. The OT
unfiltered magnitude is 13.3m (limit 17.4m). The OT is also seen in 2
images taken on 2012-08-20.542 and 20.573 UT with the same unfiltered
magnitude 13.3. Nothing was visible at this position on the unfiltered
image of 2012-08-19.521 UT to the limiting magnitude 17.5m.

The discovery and reference images are available at:
http://master.sai.msu.ru/static/OT/J17490210+1913312.jpg

There is nothing at this position in 2MASS, GCVS and AAVSO VSX. This
area is not covered by GALEX, SDSS and CRTS.

There is a star in USNO-B1.0 catalog within 2" of the OT named
USNO-B1.0 1092-0283596 with the following coordinates, proper motions
and magnitudes:
17 49 02.087 +19 13 29.52 pmRA=0 pmDE=0 B1=20.29 R1=18.64 B2=20.06
R2=17.79 I=18.64

This area was observed by the NEAT project on 12 nights from 1998 June
24 to 2005 Aug. 30. In total 36 images were taken. The object was in
outburst on 2003 Aug. 07 and then again on 2005 Aug. 13 and 30, but at
quiescence on all other images.

Based on the amplitude of variability, short rise time and presence of
previous outbursts we conclude that MASTER OT J174902.10+191331.2 is a
new cataclysmic variable (dwarf nova). Follow up observations are
encouraged.

10'x10' color-combined (BRIR) DSS finder chart is uploaded to
http://master.sai.msu.ru/static/OT/J1749+1913-BRIR10x10.jpg