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arXiv · 1312.4572

Rossby Wave Instability in Astrophysical Discs

R. V. E. Lovelace·M. M. Romanova
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Abstract

A brief review is given of the Rossby wave instability (RWI) in astrophysical discs. In non-self-gravitating discs, around for example a newly forming stars, the instability can be triggered by an axisymmetric bump at some radius $r_0$ in the disc surface mass-density. It gives rise to exponentially growing non-axisymmetric perturbation [$\propto \exp({\rm i}mϕ)$, $m=1,2..$] in the vicinity of $r_0$ consisting of {\it anticyclonic} vortices. These vortices are regions of high pressure and consequently act to trap dust particles which in turn can facilitate planetesimal growth in proto-planetary discs. The Rossby vortices in the discs around stars and black holes may cause the observed quasi-periodic modulations of the disc's thermal emission.

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R. V. E. Lovelace, M. M. Romanova. 2014-04-10. Rossby Wave Instability in Astrophysical Discs. https://doi.org/10.1088/0169-5983%2F46%2F4%2F041401

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