Jet radio emission in Cygnus X-1 and its orbital modulation

  title={Jet radio emission in Cygnus X-1 and its orbital modulation},
  author={Anna Z. Sz{\'o}stek and Andrzej A. Zdziarski},
  journal={Monthly Notices of the Royal Astronomical Society},
We present results of our detailed theoretical study of the observed orbital modulation of the radio emission in Cygnus X-1 (Cyg X-1). The modulation occurs due to free-free absorption in the wind from the companion star varying with the orbital phase, and our results put strong constraints on the spatial distribution of the jet radio emission at the frequencies of 2-15 GHz. A crucial role in enhancing the asymmetry of the wind absorption suffered by the jet emission is played by the… Expand
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