Low mass planet migration in Hall-affected disks

TL;DR

This paper investigates how low-mass planets migrate within laminar, Hall-effect influenced protoplanetary disks characterized by large-scale magnetic fields and wind-driven accretion, challenging traditional turbulent disk models.

Contribution

It provides an analytical and numerical study of planet migration in non-turbulent, magnetized disks, extending corotation torque theory to new physical conditions.

Findings

Corotation torque behavior differs significantly from turbulent disk models.

Magnetic fields and radial flows influence planet migration dynamics.

Numerical methods for inviscid problems are evaluated for accuracy and stability.

Abstract

Recent developments in non-ideal magnetohydrodynamic simulations of protoplanetary disks suggest that instead of being traditional turbulent (viscous) accretion disks, they have a largely laminar flow with accretion driven by large-scale wind torques. These disks are possibly threaded by Hall-effect generated large-scale horizontal magnetic fields. We have examined the dynamics of the corotation region of a low mass planet embedded in such a disk and the evolution of the associated migration torque. These disks lack strong turbulence and associated turbulent diffusion, and the presence of a magnetic field and radial gas flow presents a situation outside the applicability of previous corotation torque theory. We summarize the analytical analysis of the corotation torque, give details on the numerical methods used, and in particular the relative merits of different numerical schemes for the inviscid problem.