Excitation of trapped oscillations in discs around black holes

Barbara T. Ferreira; Gordon I. Ogilvie

doi:10.1063/1.3002492

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arXiv · 0810.0116

Excitation of trapped oscillations in discs around black holes

Barbara T. Ferreira·Gordon I. Ogilvie

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Abstract

High-frequency quasi-periodic oscillations detected in the light curves of black hole candidates can, according to one model, be identified with hydrodynamic oscillations of the accretion disc. We describe a non-linear coupling mechanism, suggested by Kato, through which inertial waves trapped in the inner regions of accretion discs around black holes are excited. Global warping and/or eccentricity of the disc have a fundamental role in this coupling: they combine with trapped modes, generating negative energy waves, that are damped as they approach the inner edge of the disc or their corotation resonance. As a result of this damping, inertial oscillations are amplified. We calculate the resulting eigenfunctions and their growth rates.

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Barbara T. Ferreira, Gordon I. Ogilvie. 2008-10-01. Excitation of trapped oscillations in discs around black holes. https://doi.org/10.1063/1.3002492

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