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Numerical Simulations of Rotating Accretion Flows near a Black Hole

Dongsu Ryu·Sandip K. Chakrabarti
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Abstract

We present time-dependent solutions of thin, supersonic accretion flows near a black hole and compare them with analytical solutions. Such flows of inviscid, adiabatic gas are characterized by the specific angular momentum and the specific energy. We confirm that for a wide range of above parameters a stable standing shock wave with a vortex inside it forms close to the black hole. Apart from steady state solutions, we show the existence of non-steady solutions for thin accretion flows where the accretion shock is destroyed and re-generated periodically. The unstable behavior should be caused by dynamically induced instabilities, since inviscid, adiabatic gas is considered. We discuss possible relevance of the periodic behavior on quasi-periodic oscillations (QPOs) observed in galactic and extragalactic black hole candidates.

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Dongsu Ryu, Sandip K. Chakrabarti. 1997-02-05. Numerical Simulations of Rotating Accretion Flows near a Black Hole. https://arxiv.org/abs/astro-ph/9702054

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