Astronomy and Astrophysics – Astrophysics
Scientific paper
2002-03-21
Astron.Astrophys. 396 (2002) 91-108
Astronomy and Astrophysics
Astrophysics
20 pages, 10 figures, final version, A&A accepted
Scientific paper
10.1051/0004-6361:20021339
We determine the properties of the stellar torus that we showed in a previous paper to result as a product of two merging black holes. If the surrounding stellar cluster is as massive as the binary black hole, the torque acting on the stars ejects a fraction which extracts all the binary's angular momentum on scales of ~10^7 yr, and a geometrically thick torus remains. In the present article we show that a certain fraction of the stars has winds, shaped into elongated tails by the central radiation pressure, which are optically thick for line of sights aligned with them. These stars are sufficiently numerous to achieve a covering factor of 1, so that the complete torus is optically thick. We find the parameters of such a patchy torus to be in the right range to explain the observed large column densities in AGN and their temporal variations on time scales of about a decade. Within this model the BAL quasars can be interpreted as quasars seen at intermediate inclination angles, with the line of sight grazing the edge of the torus. The opening angle of the torus is wider for major mergers and thus correlates with the central luminosity. In this picture the spin of the merged black hole is possibly dominated by the orbital angular momentum of the binary. Thus the spin of the merged black hole points into a new direction, and consequently the jet experiences a spin-flip according to the spin-paradigm. This re-orientation could be an explanation for the X-shaped radio galaxies, and the advancing of a new jet through the ambient medium for Compact Symmetric Objects.
Biermann Peter L.
Zier Christian
No associations
LandOfFree
Binary black holes and tori in AGN II. Can stellar winds constitute a dusty torus? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Binary black holes and tori in AGN II. Can stellar winds constitute a dusty torus?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Binary black holes and tori in AGN II. Can stellar winds constitute a dusty torus? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-360566