Vortex-Induced Rings and Gaps within Protoplanetary Disks

TL;DR

This paper uses 2D hydrodynamic simulations to show that vortices caused by the Rossby Wave Instability can create observable dust rings and gaps in protoplanetary disks, offering an alternative to planet-induced features.

Contribution

The study demonstrates that vortex-induced density waves are highly effective at forming dust rings and gaps, providing new insights into disk structure formation without planets.

Findings

Vortices can produce detectable dust rings and gaps in ALMA observations.

Elongated vortices create rings at larger distances from the center.

Vortex-induced density waves carry significantly more angular momentum than planet-induced waves.

Abstract

Observations of protoplanetary disks have revealed the presence of both crescent-shaped and ring-like structures in dust continuum emission. These crescents are thought to arise from dust-trapping vortices generated by the Rossby Wave Instability (RWI), which induces density waves akin to those caused by planets. These vortices have the potential to create gaps and rings within the disk, resulting from the dissipation of their density waves. We carry out 2D hydrodynamic simulations in the shearing box to investigate vortex-disk interaction. We find that long-lived vortices can produce dust rings and gaps in inviscid discs detectable by ALMA, and a more elongated vortex produces rings at larger separations. Vortex-induced density waves carry over two orders of magnitude higher angular momentum flux compared to planet-induced ones that shock at the same location, making the former much more effective at producing dust gaps and rings far away.