Instabilities at planetary gap edges in 3D self-gravitating disks

TL;DR

This study uses 3D simulations to analyze how self-gravity influences the stability and vortex formation at planetary gap edges in disks, revealing different behaviors depending on the strength of self-gravity.

Contribution

It provides new insights into the effects of self-gravity on vortex dynamics and gap stability in 3D protoplanetary disks, highlighting the suppression of vortices in strongly self-gravitating cases.

Findings

Weak self-gravity leads to vortex merging into a single large vortex.

Moderate self-gravity sustains multiple vortices over many orbits.

Strong self-gravity suppresses vortices and triggers spiral instabilities.

Abstract

Numerical simulations are presented to study the stability of gaps opened by giant planets in 3D self-gravitating disks. In weakly self-gravitating disks, a few vortices develop at the gap edge and merge on orbital time-scales. The result is one large but weak vortex with Rossby number -0.01. In moderately self-gravitating disks, more vortices develop and their merging is resisted on dynamical time-scales. Self-gravity can sustain multi-vortex configurations, with Rossby number -0.2 to -0.1, over a time-scale of order 100 orbits. Self-gravity also enhances the vortex vertical density stratification, even in disks with initial Toomre parameter of order 10. However, vortex formation is suppressed in strongly self-gravitating disks and replaced by a global spiral instability associated with the gap edge which develops during gap formation.