A new giant radio flare of V404 Cyg at centimeter wavelengths
ATel #7716; S. A. Trushkin, N. A. Nizhelskij, P. G. Tsybulev (SAO RAS, Russia)
on 26 Jun 2015; 07:41 UT
Credential Certification: Sergei Trushkin (firstname.lastname@example.org)
Subjects: Radio, Millimeter, Sub-Millimeter, Infra-Red, Optical, X-ray, Request for Observations, Binary, Black Hole, Nova, Transient
In following monitoring of the all-band fast-changing activity in V404 Cyg (ATel #7667) we detected the giant flare with RATAN-600 radio telescope. The measured fluxes are 2.34 +- 0.2 Jy, 3.36 +- 0.1 Jy, 3.82 +- 0.1 Jy, 3.70 +- 0.1 Jy and 2.84 +- 0.2 Jy at 2.3, 4.6, 8.2, 11.2 and 21.7 GHz at MJD57198.933 (22:23UTC 25 June) i.e. fluxes rose from by ~11-60 times from previous measurements a day ago. The spectrum has a notable turnover at the lower frequencies and a spectral index is equal to -0.4 between 11.2 and 21.7 GHz. The fluxes are much higher than in the powerful transient event of 1989 (Han and Hjellming, 1992) and are comparable with recent SMA measurements at 230 GHz (~6 Jy, ATel #7708). The daily updated measured spectra of V404 Cyg could be found with the link in our ATel #7667.
The RATAN-600 light curves of V404 Cyg in 2015