Global Simulations of the Vertical Shear Instability with Non-ideal Magnetohydrodynamical Effects

TL;DR

This study uses 2D global non-ideal MHD simulations to explore how vertical shear instability interacts with magnetized disk winds in protoplanetary disks, revealing coexistence and effects on turbulence and accretion.

Contribution

It provides the first detailed analysis of the interplay between VSI and MHD winds in PPDs under non-ideal MHD effects, highlighting their coexistence and mutual influence.

Findings

MHD winds can coexist with VSI in PPDs.

VSI turbulence remains similar to unmagnetized cases.

Magnetization weakens VSI and induces breathing mode oscillations.

Abstract

The mechanisms of angular momentum transport and level of turbulence in protoplanetary disks (PPDs) are crucial for understanding many aspects of planet formation. In the recent years, it has been realized that the magneto-rotational instability (MRI) tends to be suppressed in PPDs due to non-ideal MHD effects, and the disk is largely laminar with accretion driven by magnetized disk winds. In parallel, several hydrodynamical mechanisms have been identified that likely also generate vigorous turbulence and drive disk accretion. We study the interplay between MHD winds in PPDs with the vertical shear instability (VSI), one of the most promising hydrodynamical mechanisms, through 2D global non-ideal MHD simulations with ambipolar diffusion and Ohmic resistivity. We find that for typical disk parameters, MHD winds can coexist with the VSI with accretion primarily wind-driven accompanied by vigorous VSI turbulence. The properties of the VSI remain similar to unmagnetized case, and the wind and overall field configuration are not strongly affected by VSI turbulence, showing modest level of variability and corrugation of midplane current sheet. Enhanced coupling between gas and magnetic field weakens the VSI. The VSI is also weakened with increasing magnetization, and we find that corrugation motions characteristic of the VSI transitions to low-amplitude breathing mode oscillations.