[vsnet-alert 16930] New bright CV in Auriga MASTER OT J055845.55+391533.4

[Denis Denisenko]

I have found new bright CV in MASTER-Amur transients with a number of
previous outbursts in archival data as bright as 13.8-13.9m. It was
published in ATel #5905
<http://www.astronomerstelegram.org/?read=5905> together with another
(fainter) transient.

MASTER OT J055845.55+391533.4
  20140219.446  14.45C  MASTER-Amur
  20140219.477  14.45C  MASTER-Amur

Checking MASTER-Tunka database we have found that the outburst had
started at least 6 days ago, on 2014 Feb. 13:

MASTER OT J055845.55+391533.4
  20140213.579  13.93C  MASTER-Tunka
  20140213.581  13.87C  MASTER-Tunka
  20140213.583  13.98C  MASTER-Tunka
  20140213.624  13.92C  MASTER-Tunka
  20140213.626  13.90C  MASTER-Tunka
  20140213.628  13.89C  MASTER-Tunka

The object was bright (14.8m) on MASTER-Tunka reference image from
2011, this is why it has not satisfied the transient detection
criterion and the robot in Tunka has missed this outburst! Luckily we
caught it with another system.

IDs in catalogs:
USNO-B1.0 1292-0151637 (05 58 45.481 +39 15 32.61 pmRA=0 pmDE=0
B1=17.33 R1=18.47 B2=13.79 R2=17.43 I=17.30)
GALEX J055845.5+391533 (NUV=19.02+/-0.09)
GALEX J055845.6+391534 (NUV=19.09+/-0.11)

Color-combined DSS finder chart:
http://master.sai.msu.ru/static/OT/J055845+391533-BRIR5x5.jpg

The object was in outburst on the 2nd epoch Palomar Blue plate of
1990-01-25, hence the unnatural color. Comparison of POSS-I and
POSS-II blue plates:
http://master.sai.msu.ru/static/OT/J055845+391533-POSS-B.jpg

Photometric time series are encouraged.

Denis Denisenko
Member of MASTER team at SAI MSU