BLACK HOLE, JET, AND DISK: THE UNIVERSAL ENGINE

BLACK HOLE, JET, AND DISK: THE UNIVERSAL ENGINE

Heino Falcke (1,2)

(1) Max-Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany

(2) Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA

in: ``Jets from Stars and Galactic Nuclei'', Lecture Notes in Physics 471, W. Kundt (ed.), Springer, p. 19-34


Abstract:

In this paper I review the results of our ongoing project to investigate the coupling between accretion disk and radio jet in galactic nuclei and stellar mass black holes. We find a good correlation between the UV bump luminosity and the radio luminosities of AGN, which improves upon the usual OIII/radio correlations. Taking mass and energy conservation in the jet/disk system into account we can successfully model the correlation for radio-loud and radio-weak quasars. We find that jets are comparable in power to the accretion disk luminosity, and the difference between radio-loud and radio-weak may correspond to two natural stages of the relativistic electron distribution - assuming that radio weak quasars have jets as well. The distribution of flat- and steep-spectrum sources is explained by bulk Lorentz factors gamma_j ~ 5-10. The absence of radio-loud quasars below a critical optical luminosity coincides with the FR I/FR II break and could be explained by a powerdependent, ``closing'' torus. This points towards a different type of obscuring torus in radio-loud hostgalaxies which might be merger related (e.g. by the formation of a temporary binary black-hole). Interaction of the jet with the closing torus might in principle also help to make a jet radio-loud. Turning to stellar-mass black holes we find that galactic jet sources can be described with the same coupled jet/disk model as AGN which is suggestive of some kind of universal coupling between jet and accretion disk around compact objects.


Paper: Also available in PostScript and Tex (Springer lecproc.cmm) Format.

Other publications can be found here.

Questions: Heino Falcke, hfalcke@astro.umd.edu