Disk-Planet Interactions During Planet Formation

TL;DR

This paper reviews the mechanisms of disk-planet interactions during planet formation, highlighting recent advances in numerical simulations that reveal new migration regimes and potential ways to slow or reverse inward planetary migration.

Contribution

It introduces recent numerical techniques and findings that suggest possible slowing or reversal of planetary migration, including the discovery of a new type III migration regime.

Findings

Identification of a new type III migration regime

Indications that inward migration can be slowed or reversed

Advances in high-resolution numerical simulations of disk-planet interactions

Abstract

The discovery of close orbiting extrasolar giant planets led to extensive studies of disk planet interactions and the forms of migration that can result as a means of accounting for their location. Early work established the type I and type II migration regimes for low mass embedded planets and high mass gap forming planets respectively. While providing an attractive means of accounting for close orbiting planets intially formed at several AU, inward migration times for objects in the earth mass range were found to be disturbingly short, making the survival of giant planet cores an issue. Recent progress in this area has come from the application of modern numerical techniques which make use of up to date supercomputer resources. These have enabled higher resolution studies of the regions close to the planet and the initiation of studies of planets interacting with disks undergoing MHD turbulence. This work has led to indications of how the inward migration of low to intermediate mass planets could be slowed down or reversed. In addition, the possibility of a new very fast type III migration regime, that can be directed inwards or outwards, that is relevant to partial gap forming planets in massive disks has been investigated.