Dual black holes in merger remnants. I: linking accretion to dynamics

Details Dual black holes in merger remnants. I: linking accretion to dynamics Dual black holes in merger remnants. I: linking accretion to dynamics

2009-02-09

arxiv.org/abs/0902.1525v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

8 pages, 4 figures, revised version accepted to MNRAS

Scientific paper

We study the orbital evolution and accretion history of massive black hole (MBH) pairs in rotationally supported circumnuclear discs up to the point where MBHs form binary systems. Our simulations have high resolution in mass and space which, for the first time, makes it feasible to follow the orbital decay of a MBH either counter- or co-rotating with respect to the circumnuclear disc. We show that a moving MBH on an initially counter-rotating orbit experiences an "orbital angular momentum flip" due to the gas-dynamical friction, i.e., it starts to corotate with the disc before a MBH binary forms. We stress that this effect can only be captured in very high resolution simulations. Given the extremely large number of gas particles used, the dynamical range is sufficiently large to resolve the Bondi-Hoyle-Lyttleton radii of individual MBHs. As a consequence, we are able to link the accretion processes to the orbital evolution of the MBH pairs. We predict that the accretion rate is significantly suppressed and extremely variable when the MBH is moving on a retrograde orbit. It is only after the orbital angular momentum flip has taken place that the secondary rapidly "lights up" at which point both MBHs can accrete near the Eddington rate for a few Myr. The separation of the double nucleus is expected to be around ~10 pc at this stage. We show that the accretion rate can be highly variable also when the MBH is co-rotating with the disc (albeit to a lesser extent) provided that its orbit is eccentric. Our results have significant consequences for the expected number of observable double AGNs at separations of <100 pc.

Affiliated with

Also associated with

No associations

Rating

Dual black holes in merger remnants. I: linking accretion to dynamics 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 Dual black holes in merger remnants. I: linking accretion to dynamics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual black holes in merger remnants. I: linking accretion to dynamics will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-19255