[vsnet-outburst 18366] V404 Cyg outburst

[Taichi Kato]

V404 Cyg outburst

   V404 Cyg is an X-ray transient (black-hole binary) which
underwent outbursts in 1938, 1956, 1979? and 1989
(see Richter IBVS No.3362, 1989).  This object has been
intensively monitored since (also by X-ray satellites).
So the present outburst interval is nearly 26 years!

   At the time of ther 1989 outburst, CCD observations
were not so popular and only a small amount of time-series
photometry was published.  We now have a chance to confirm
short-term variation reported both in X-rays and the optical
(e.g. Casares et al. 1991 MNRAS 250, 715 and other papers).
There have been several papers reporting periods of several
hours (also in quiescence).  We also have a chance to detect
potential superhumps (but the orbital period is long: 6.5 d).

   Usual time-series photometry is required as in CVs.
The object is, however, highly reddened, and it would be
recommended to use filters (if possible) and multicolor
observations are recommended.  The object is brightest
in I-band and would be an easy target.

===

Outburst confirmed, just measured V0404 Cyg at 13.1V

Douglas.

----- Original Message ----- 
  From: 'Eddy Muyllaert' eddy.muyllaert at skynet.be [baavss-alert] 
  To: cvnet-outburst ; baavss-alert 
  Sent: Tuesday, June 16, 2015 10:24 PM
  Subject: [baavss-alert] V404 Cyg going into outburst!?


    

  V404 CYG        2015 Jun 16.1688          16.18C  OUTBURST !?

  Definitially brighter than in its quiescence!

  Bradford Robotic Telescope

  Regards,

  Eddy