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Radiation-Driven Warping: The Origin of Warps and Precession in Accretion Disks

Philip R. Maloney·Mitchell C. Begelman·J. E. Pringle
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Abstract

A geometrically thin, optically thick, warped accretion disk with a central source of luminosity is subject to non-axisymmetric forces due to radiation pressure; the resulting torque acts to modify the warp. In a recent paper, \cite{pri96} used a local analysis to show that initially planar accretion disks are unstable to warping driven by radiation torque. Here we extend this work with a global analysis of the stable and unstable modes. We confirm Pringle's conclusion that thin centrally-illuminated accretion disks are generically unstable to warping via this mechanism; we discuss the time-evolution and likely steady-state of such systems and show specifically that this mechanism can explain the warping of the disk of water masers in NGC 4258 and the 164-day precession period of the accretion disk in SS 433. Radiation-driven warping and precession provides a robust mechanism for producing warped, precessing accretion disks in active galactic nuclei and X-ray binary systems.

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Philip R. Maloney, Mitchell C. Begelman, J. E. Pringle. 1996-12-11. Radiation-Driven Warping: The Origin of Warps and Precession in Accretion Disks. https://doi.org/10.1086/178089

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