THE X-RAY CORONA AND JET OF CYGNUS X-1

Julien Malzac (1) , Renaud Belmont (1)

1 CESR - Centre d'étude spatiale des rayonnements

Evidence is presented indicating that in the hard state of Cygnus X-1, the coronal mag- netic field might be below equipartition with radiation (suggesting that the corona is not powered by magnetic field dissipation) and that the ion temperature in the corona is significantly lower than what predicted by ADAF like models. It is also shown that the current estimates of the jet power set interesting contraints on the jet velocity (which is at least mildly relativistic), the accretion efficiency (which is large in both spectral states), and the nature of the X-ray emitting region (which is unlikely to be the jet).

Mots clés: Black holes; Accretion; accretion discs; X-rays: binaries; gamma rays: theory; Jets

Domaines: Phénomènes cosmiques de haute energie [astro-ph.HE]; Phénomènes cosmiques de haute energie [astro-ph.HE]

Julien Malzac, Renaud Belmont. THE X-RAY CORONA AND JET OF CYGNUS X-1. 2010. ⟨hal-00483578⟩