1. The giant radio flare of Cygnus X-3 in September 2016
- Author
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Trushkin, S. A., Nizhelskij, N. A., Tsybulev, P. G., and Zhekanis, G. V.
- Subjects
High Energy Astrophysical Phenomena (astro-ph.HE) ,Astrophysics - Solar and Stellar Astrophysics ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics - High Energy Astrophysical Phenomena ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
In the long-term multi-frequency monitoring program of the microquasars with RATAN-600 we discovered the giant flare from the X-ray binary Cygnus X-3 on 13 September 2016. It happened after 2000 days of the 'quiescent state' of the source passed after the former giant flare (~18 Jy) in March 2011. We have found that during this quiet period the hard X-ray flux (Swift/BAT, 15-50 keV) and radio flux (RATAN-600, 11 GHz) have been strongly anti-correlated. Both radio flares occurred after transitions of the microquasar to a 'hypersoft' X-ray state that occurred in February 2011 and in the end of August 2016. The giant flare was predicted by us in the first ATel #9416. Indeed after dramatic decrease of the hard X-ray Swift 15-50 keV flux and RATAN 4-11 GHz fluxes (a 'quenched state') a small flare (0.7 Jy at 4-11 GHz) developed on MJD 57632 and then on MJD 57644.5 almost simultaneously with X-rays radio flux rose from 0.01 to 15 Jy at 4.6 GHz during few days. The rise of the flaring flux is well fitted by a exponential law that could be a initial phase of the relativistic electrons generation by internal shock waves in the jets. Initially spectra were optically thick at frequencies lower 2 GHz and optically thin at frequencies higher 8 GHz with typical spectral index about -0.5. After maximum of the flare radio fluxes at all frequencies faded out with the exponential law (~ exp(-(t-t0)/2d) for 21.7 GHz)., 4 pages, 3 figures, in Stars: from collapse to collapse. Proceedings of the International Conference held in Nizhnij Arkhyz, Karachai-Cherkessian Republic, Special Astrophysical Observatory RAS, October 3-7, 2016, ASP Conf. Ser. 2017 (in press)
- Published
- 2016