The magnetisation of protoplanetary disks
نویسنده
چکیده
The remanent magnetisation of meteorite material in the solar system indicates that magnetic fields of several Gauss are present in the protoplanetary disk. It is shown that such relatively strong magnetic fields can be generated in dusty protoplanetary disks by relative shear motions of the charged dust and the neutral gas components. Self-consistent multi-fluid simulations show that for typical plasma parameters shear flows with collisional momentum transfer between the different components of the dusty plasma result in a very efficient generation of magnetic fields with strengths of about 0.1-1 Gauss on spatial scales of two astronomical units in about one year. Based on the simulations one may predict that future measurements will reveal the strong magnetisation of circumstellar disks around young stellar objects.
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