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Numerical simulations of the accretion-ejection instability

Stuart Caunt·Michel Tagger
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Abstract

The Accretion-Ejection Instability (AEI) is explored numerically using a global 2d model of the inner region of a magnetised accretion disk. The disk is initially currentless but threaded by an external vertical magnetic field created by external currents, and frozen in the flow. In agreement with the theory a spiral instability, similar in many ways to those observed in self-gravitating disks, but driven by magnetic stresses, develops when the magnetic field is close to equipartition with the disk thermal pressure. The present non-linear simulations give good evidence that such an instability can occur in the inner region of accretion disks.

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Stuart Caunt, Michel Tagger. 2000-11-17. Numerical simulations of the accretion-ejection instability. https://arxiv.org/abs/astro-ph/0011336

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