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Recurrent microblazar activity in Cygnus X-1?

G. E. Romero·M. M. Kaufman Bernado·I. F. Mirabel
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Abstract

Recurrent flaring events at X- and soft gamma-ray energies have been recently reported for the galactic black hole candidate Cygnus X-1. The observed fluxes during these transient outbursts are far higher than what is observed in ``normal'' episodes. Here we suggest that the origin of this radiation is non-thermal and produced by inverse Compton interactions between relativistic electrons in the jet and external photon fields, with a dominant contribution from the companion star field. The recurrent and relatively rapid variability could be explained by the precession of the jet, which results in a variable Doppler amplification.

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G. E. Romero, M. M. Kaufman Bernado, I. F. Mirabel. 2002-08-28. Recurrent microblazar activity in Cygnus X-1?. https://doi.org/10.1051/0004-6361%3A20021205

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