Marcelo Ponce, Joshua A. Faber, James C. Lombardi Jr
Numerical calculations of merging black hole binaries indicate that
asymmetric emission of gravitational radiation can kick the merged black hole
at up to thousands of km/s, and a number of systems have been observed recently
whose properties are consistent with an active galactic nucleus containing a
supermassive black hole moving with substantial velocity with respect to its
broader accretion disk. We study here the effect of an impulsive kick delivered
to a black hole on the dynamical evolution of its accretion disk using a
smoothed particle hydrodynamics code, focusing attention on the role played by
the kick angle with respect to the orbital angular momentum vector of the
pre-kicked disk. We find that for more vertical kicks, for which the angle
between the kick and the normal vector to the disk $\theta\lesssim 30^\circ$, a
gap remains present in the inner disk, in accordance with the prediction from
an analytic collisionless Keplerian disk model, while for more oblique kicks
with $\theta\gtrsim 45^\circ$, matter rapidly accretes toward the black hole.
There is a systematic trend for higher potential luminosities for more oblique
kick angles for a given black hole mass, disk mass and kick velocity, and we
find large amplitude oscillations in time in the case of a kick oriented
$60^\circ$ from the vertical.
View original:
http://arxiv.org/abs/1107.1711
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