Penetration of Magneto-Rotationally Unstable Perturbations in SSD into ADAF through a Transition Surface
نویسنده
چکیده
A linear deformation, by a magneto-rotational instability, of the transition suface between an outer Shakura-Sunyaev-type standard disk (SSD) and inner advection-dominated accretion flows (ADAF) is examined. The transition is assumed to be a discontinuous plane where a low-temperature, high-density gas is jointed to a high-temperature, low-density gas. No mass flow through the surface is considered. Magnetic fields directed in the vertical direction are assumed. We examine how the linear perturbations generated by the magneto-rotational instability in the outer region penetrate into the inner region. The perturbation penetrates into the inner region with an exponentially decreasing amplitude. We suppose that the perturbations of MHD turbulence invading into the inner ADAF region from the outer SSD region would be seed fluctuations of the strong time variabilities observed in the high state of X-ray black-hole candidates.
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