Journal
ASTROPHYSICAL JOURNAL
Volume 706, Issue 1, Pages 705-711Publisher
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/706/1/705
Keywords
accretion, accretion disks; black hole physics; MHD; turbulence; waves; X-rays: binaries
Categories
Funding
- NSF [AST-0707624, AST-0807385]
- FCT (Portugal) [SFRH/BD/22251/2005]
- American Astronomical Society International Travel Grant
- Fundação para a Ciência e a Tecnologia [SFRH/BD/22251/2005] Funding Source: FCT
Ask authors/readers for more resources
We analyze the time dependence of fluid variables in general relativistic, magnetohydrodynamic simulations of accretion flows onto a black hole with dimensionless spin parameter a/M = 0.9. We consider both the cases where the angular momentum of the accretion material is aligned with the black hole spin axis (an untilted flow) and where it is misaligned by 15 degrees (a tilted flow). In comparison to the untilted simulation, the tilted simulation exhibits a clear excess of inertial variability, that is, variability at frequencies below the local radial epicyclic frequency. We further study the radial structure of this inertial-like power by focusing on a radially extended band at 118(M/10 M(circle dot))(-1) Hz found in each of the three analyzed fluid variables. The three-dimensional density structure at this frequency suggests that the power is a composite oscillation whose dominant components are an over dense clump corotating with the background flow, a low-order inertial wave, and a low-order inertial-acoustic wave. Our results provide preliminary confirmation of earlier suggestions that disk tilt can be an important excitation mechanism for inertial waves.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available