Poster Talk abstract details
3D global MHD simulations of the proto-planetary disks with the dead zone.
Abstract
We present 3D global simulations of MHD turbulence in proto-planetary disks (PPds).
The disk in our models has 4 pressure scale heights. The radial extension is up to 10 AU, including a 'dead' zone with low ionization at the midplane due to the presence of the dust grains. We take into account the presence of icy dust grains, as magnetic diffusivity is one order of magnitude higher in the disk part beyond the 'snow'-line, which locates the border of water sublimation in the PPds. To perform non-ideal MHD simulations, we use ZeusMP code. We concentrate on gas dynamics and magneto-rotational instability (MRI), whereas temperature and magnetic diffusivity are fixed parameters.
The magnetic diffusion varies from $10^{-10}$ at 4 scale heights to 1.6$10^{-2}$ [$\rm AU^2/yr$]
at the midplane. Turbulent stresses are nevertheless non-zero at the midplane, growing exponentially towards the disk corona.
We have found that MRI turbulence leads to large-scale magnetic fields. In the dead zone the azimuthal magnetic field survives. The symmetry of the magnetic field and the gas flow with respect to the midplane depends strongly on the choice of boundary conditions.
The disk in our models has 4 pressure scale heights. The radial extension is up to 10 AU, including a 'dead' zone with low ionization at the midplane due to the presence of the dust grains. We take into account the presence of icy dust grains, as magnetic diffusivity is one order of magnitude higher in the disk part beyond the 'snow'-line, which locates the border of water sublimation in the PPds. To perform non-ideal MHD simulations, we use ZeusMP code. We concentrate on gas dynamics and magneto-rotational instability (MRI), whereas temperature and magnetic diffusivity are fixed parameters.
The magnetic diffusion varies from $10^{-10}$ at 4 scale heights to 1.6$10^{-2}$ [$\rm AU^2/yr$]
at the midplane. Turbulent stresses are nevertheless non-zero at the midplane, growing exponentially towards the disk corona.
We have found that MRI turbulence leads to large-scale magnetic fields. In the dead zone the azimuthal magnetic field survives. The symmetry of the magnetic field and the gas flow with respect to the midplane depends strongly on the choice of boundary conditions.