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Magnetized Accretion Inside the Marginally Stable Orbit around a Black Hole

J. H. Krolik
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Abstract

Qualitative arguments are presented to demonstrate that the energy density of magnetic fields in matter accreting onto a black hole inside the marginally stable orbit is automatically comparable to the rest-mass energy density of the accretion flow. Several consequences follow: magnetic effects must be dynamically significant, but cannot be so strong as to dominate; outward energy transport in Alfven waves may alter the effective efficiency of energy liberation; and vertical magnetic stresses in this region may contribute to "coronal" activity.

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J. H. Krolik. 1999-02-18. Magnetized Accretion Inside the Marginally Stable Orbit around a Black Hole. https://doi.org/10.1086/311979

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