The beginning of a giant radio flare from Cygnus X-3
ATel #9444; S. A. Trushkin, N. A. Nizhelskij, P. G. Tsybulev, G. V. Zhekanis (SAO RAS, Russia)
on 1 Sep 2016; 13:29 UT
Credential Certification: Sergei Trushkin (email@example.com)
Subjects: Radio, Millimeter, Sub-Millimeter, Infra-Red, X-ray, Gamma Ray, >GeV, VHE, Binary, Black Hole, Transient
As we suggested in ATel #9416, galactic microquasar Cygnus X-3 is currently undergoing a flaring activity. If on 30 August 2016 (MJD 57630.798) its fluxes were 120-128 mJy at 4.6, 8.2, 11.2 GHz in the RATAN-600 radio telescope observations, then on 31 August (MJD 57631.795) the fluxes became 60, 300, 570, 740, 800 mJy at 2.3, 4.6, 8.2, 11.2 and 21.7 GHz with typical errors about 3-7%. Such spectrum is characterized optically thick synchrotron emission at frequencies lower 4-6 GHz and optically thin emission higher 8-10 GHz. It is usual for compact relativistic jets or a beginning of the ejection and it has been met a few times in the multi-frequency light curves of Cygnus X-3 (see ATel #1881). We suggest that the flare will be evolve to the higher fluxes and the multi-frequency monitoring and especially the VLBI mapping of the source will be very relevant. We updated (and will do) the light curves on the plot from ATel #9416.
Radio spectra of Cyg X-3 on 30-31 Aug 2016