Magnetized Accretion Inside the Marginally Stable Orbit around a Black Hole
نویسنده
چکیده
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 Alfvén waves may alter the effective efficiency of energy liberation; and vertical magnetic stresses in this region may contribute to “coronal” activity. Subject headings: accretion, accretion disks, black holes, MHD
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