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Shakura-Sunyaev Disk Can Smoothly Match Advection-Dominated Accretion Flow

Ju-Fu Lu·Yi-Qing Lin·Wei-Min Gu
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Abstract

We use the standard Runge-Kutta method to solve the set of basic equations describing black hole accretion flows composed of two-temperature plasma. We do not invoke any extra energy transport mechanism such as thermal conduction and do not specify any ad hoc outer boundary condition for the advection-dominated accretion flow (ADAF) solution. We find that in the case of high viscosity and non-zero radiative cooling, the ADAF solution can have an asymptotic approach to the Shakura-Sunyaev disk (SSD) solution, and the SSD-ADAF transition radius is close to the central black hole. Our results further prove the mechanism of thermal instability-triggered SSD-ADAF transition suggested previously by Takeuchi & Mineshige and Gu & Lu.

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Ju-Fu Lu, Yi-Qing Lin, Wei-Min Gu. 2004-01-04. Shakura-Sunyaev Disk Can Smoothly Match Advection-Dominated Accretion Flow. https://doi.org/10.1086/382209

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