Planet Migration in Protoplanetary Disks with Rims

TL;DR

This study uses hydrodynamic simulations to explore how disk structures like edges and rings influence the migration and retention of different planet types, revealing observational patterns and feedback effects on disk profiles.

Contribution

It demonstrates the impact of disk features on planet migration and retention, highlighting the role of surface density gradients and feedback mechanisms in planet-disk interactions.

Findings

Gas giants tend to migrate away from sharp disk edges.

Super-Earths are often retained in bright rings.

Jupiters are more likely found in dark rings (gaps).

Abstract

Complex structures, including sharp edges, rings and gaps, have been commonly observed in protoplanetary disks with or without planetary candidates. Here we consider the possibility that they are the intrinsic consequences of angular momentum transfer mechanisms, and investigate how they may influence the dynamical evolution of embedded planets. With the aid of numerical hydrodynamic simulations, we show that gas giants have a tendency to migrate away from sharp edges, whereas super-Earths embedded in the annuli tend to be retained. This implies that, observationally, Jupiters are preferentially detected in dark rings (gaps), whereas super-Earths tend to be found in bright rings (density bumps). Moreover, planets' tidal torque provide, not necessarily predominant, feedback on the surface density profile. This tendency implies that Jupiter's gap-opening process deepens and widens the density gap associated with the dark ring, while super-Earths can be halted by steep surface density gradient near the disk or ring boundaries. 13Hence, we expect there would be a desert for super-Earths in the surface density gap.