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Oscillations of Thick Accretion Discs Around Black Holes

Eduardo Rubio-Herrera·William H. Lee
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Abstract

We present a numerical study of the response of a thick accretion disc to a localized, external perturbation with the aim of exciting internal modes of oscillation. We find that the perturbations efficiently excite global modes recently identified as acoustic p--modes, and closely related to the epicyclic oscillations of test particles. The two strongest modes occur at eigenfrequencies which are in a 3:2 ratio. We have assumed a constant specific angular momentum distribution within the disc. Our models are in principle scale--free and can be used to simulate accretion tori around stellar or super massive black holes.

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Eduardo Rubio-Herrera, William H. Lee. 2004-11-23. Oscillations of Thick Accretion Discs Around Black Holes. https://doi.org/10.1111/j.1745-3933.2005.00011.x

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