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arXiv · 1611.09533

Toward realistic simulations of magneto-thermal winds from weakly-ionized protoplanetary disks

Oliver Gressel
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Abstract

Protoplanetary disks (PPDs) accrete onto their central T Tauri star via magnetic stresses. When the effect of ambipolar diffusion (AD) is included, and in the presence of a vertical magnetic field, the disk remains laminar between 1-5 au, and a magnetocentrifugal disk wind forms that provides an important mechanism for removing angular momentum. We present global MHD simulations of PPDs that include Ohmic resistivity and AD, where the time-dependent gas-phase electron and ion fractions are computed under FUV and X-ray ionization with a simplified recombination chemistry. To investigate whether the mass loading of the wind is potentially affected by the limited vertical extent of our existing simulations, we attempt to develop a model of a realistic disk atmosphere. To this end, by accounting for stellar irradiation and diffuse reprocessing of radiation, we aim at improving our models towards more realistic thermodynamic properties.

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Oliver Gressel. 2016-11-29. Toward realistic simulations of magneto-thermal winds from weakly-ionized protoplanetary disks. https://doi.org/10.1088/1742-6596/837/1/012008

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