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arXiv · 0801.1960

Magnetic shear-driven instability and turbulent mixing in magnetized protostellar disks

Alfio Bonanno·Vadim Urpin
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Abstract

Observations of protostellar disks indicate the presence of the magnetic field of thermal (or superthermal) strength. In such a strong magnetic field, many MHD instabilities responsible for turbulent transport of the angular momentum are suppressed. We consider the shear-driven instability that can occur in protostellar disks even if the field is superthermal. This instability is caused by the combined influence of shear and compressibility in a magnetized gas and can be an efficient mechanism to generate turbulence in disks. The typical growth time is of the order of several rotation periods.

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Alfio Bonanno, Vadim Urpin. 2008-01-13. Magnetic shear-driven instability and turbulent mixing in magnetized protostellar disks. https://doi.org/10.1051/0004-6361:20077562

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