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arXiv · 1902.11073

Generalised warped disk equations

Rebecca G. Martin·Stephen H. Lubow·J. E. Pringle·Alessia Franchini·Zhaohuan Zhu·Stephen Lepp·Rebecca Nealon·C. J. Nixon·David Vallet
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Abstract

The manner in which warps in accretion disks evolve depends on the magnitude of the viscosity. For small viscosity $(\alpha < H/R)$ the warp evolves in a wave-like manner; for large viscosity $H/R<\alpha \ll 1$ it evolves diffusively. Here $\alpha$ is the viscosity parameter and $H/R$ the disk aspect ratio. Currently there is no simple set of equations which describes the evolution in both regimes. In this paper we describe a possible solution to this problem and introduce a set of one-dimensional equations that describe the evolution of a warped disk that are applicable in both high and low viscosity regimes for arbitrary tilts, but small warps.

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Rebecca G. Martin, Stephen H. Lubow, J. E. Pringle, Alessia Franchini, Zhaohuan Zhu, Stephen Lepp, Rebecca Nealon, C. J. Nixon, David Vallet. 2019-02-28. Generalised warped disk equations. https://doi.org/10.3847/1538-4357/ab0bb7

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