The magnetorotational instability across the dead zone of protoplanetary disks
نویسنده
چکیده
The magnetorotational instability across the dead zone of protoplanetary disks
منابع مشابه
Self-Sustained Ionization and Vanishing Dead Zones in Protoplanetary Disks
We analyse the ionization state of the magnetohydrodynamically turbulent protoplanetary disks and propose a new mechanism of sustaining ionization. First, we show that in the quasi-steady state of turbulence driven by magnetorotational instability in a typical protoplanetary disk with dust grains the amount of energy dissipation should be sufficient for providing the ionization energy that is r...
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Previous models of dust growth in protoplanetary disks considered either uniformly laminar or turbulent disks. This Letter explores how dust growth occurs in a layered protoplanetary disk in which the magnetorotational instability generates turbulence only in the surface layers of a disk. Two cases are considered: a completely laminar dead zone and a dead zone in which turbulence is “stirred up...
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Context. Recent observations of the X–ray emission from T Tauri stars in the Orion nebula have shown that they undergo frequent outbursts in their X–ray luminosity. These X–ray flares are characterised by increases in luminosity by two orders of magnitude, a typical duration of less than one day, and a significant hardening of the X–ray spectrum. Aims. It is unknown what effect these X–ray flar...
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We investigate fluid motions near the midplane of vertically stratified accretion disks with highly resistive midplanes. In such disks, the magnetorotational instability drives turbulence in thin layers surrounding a resistive, stable dead zone. The turbulent layers in turn drive motions in the dead zone. We examine the properties of these motions using three-dimensional, stratified, local, she...
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Migration of protoplanets in their gaseous host disks may be largely responsible for the observed orbital distribution of extrasolar planets. Recent simulations have shown that the magnetorotational turbulence thought to drive accretion in protoplanetary disks can affect migration by turning it into an orbital random walk. However, these simulations neglected the disk’s ionization structure. Lo...
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