English

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

Earth and Planetary Astrophysics 2020-03-11 v3 Solar and Stellar Astrophysics

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.

Keywords

Cite

@article{arxiv.1912.02941,
  title  = {Global Simulations of the Vertical Shear Instability with Non-ideal Magnetohydrodynamical Effects},
  author = {Can Cui and Xue-Ning Bai},
  journal= {arXiv preprint arXiv:1912.02941},
  year   = {2020}
}

Comments

19 pages, 16 figures, accepted for publication in ApJ