[ Previous | Next | ADS ]

Ongoing radio monitoring of Cyg X-3 with the RATAN-600 radio telescope

ATel #10126; S. A. Trushkin, N. A. Nizhelskij, P. G. Tsybulev, G. V. Zhekanis (SAO RAS, Russia)
on 25 Feb 2017; 12:35 UT
Credential Certification: Sergei Trushkin (satr@sao.ru)

Subjects: Radio, Millimeter, Sub-Millimeter, Infra-Red, X-ray, Gamma Ray, >GeV, VHE, Request for Observations, Black Hole

Referred to by ATel #: 10138, 10243, 10252, 10257, 10274

Based on the X-ray and radio data Trushkin et al. (ATel #9416, #9444) predicted and then 20 days later detected (ATel #9501) the giant flare from Cyg X-3 in September 2016. During last months we continued the daily multi-frequency monitoring of Cyg X-3 with RATAN-600. Recently Loh et al. (ATel #10109) have justifiably announced that Cyg X-3 have again entered in an ultra soft X-ray state (Koljonen et al. 2010; Corbel et al. 2012) and they detected the enhanced gamma-ray emission around MJD 57799. The radio fluxes have changed in the faint flares and fadings just after MJD 57790. We have measured the maximal flux densities of 800 +/- 30 mJy at 4.6 and 8.2 GHz on MJD 57806.318 but later fluxes decreased to 100-300 mJy on MJD 57808.312. The current state of Cyg X-3 is very similar on its state on MJD 57632 (see the figure below), 20 days before maximum of the giant flare in September 2016. Thus it is very probably that a new giant radio flare will occur during next 10-20 days.

The RATAN multi-frequency light curves and Swift/BAT data at 15-50 keV of Cyg X-3 during last 200 days in 2016-2017