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The Power of Jets: New Clues from Radio Circular Polarization and X-rays

Heino Falcke·Thomas Beckert·Sera Markoff·Elmar Koerding·Geoffrey C. Bower·Rob Fender
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Abstract

Jets are ubiquitous in accreting black holes. Often ignored, they may be a major contributor to the emitted spectral energy distribution for sub-Eddington black holes. For example, recent observations of radio-to-X-ray correlations and broad band spectra of X-ray binaries in the low/hard state can be explained by a significant synchrotron contribution from jets also to their IR-to-X-ray spectrum as proposed by Markoff, Falcke, Fender 2001. This model can also explain state-transitions from low/hard to high/soft states. Relativistic beaming of the jet X-ray emission could lead to the appearance of seemingly Super-Eddington X-rays sources in other galaxies. We show that a simple population synthesis model of X-ray binaries with relativistic beaming can well explain the currently found distribution of off-nucleus X-ray point sources in nearby galaxies. Specifically we suggest that the so-called ultra-luminous X-ray sources (ULXs, also IXOs) could well be relativistically beamed microblazars. The same model that can be used to explain X-ray binaries also fits Low-Luminosity AGN (LLAGN) and especially Sgr A* in the Galactic Center. The recent detection of significant circular polarization in AGN radio cores, ranging from bright quasars down to low-luminosity AGN like M81*, Sgr A* and even X-ray binaries, now places additional new constraints on the matter contents of such jets. The emerging picture are powerful jets with a mix of hot and cold matter, a net magnetic flux, and a stable magnetic north pole.

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Heino Falcke, Thomas Beckert, Sera Markoff, Elmar Koerding, Geoffrey C. Bower, Rob Fender. 2001-11-19. The Power of Jets: New Clues from Radio Circular Polarization and X-rays. https://doi.org/10.1007/10856495_61

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