Modelling magnetised accretion discs
نویسنده
چکیده
Some recent results are reviewed that lead us now to believe that accretion discs are basically always magnetised. The main components are Balbus-Hawley and Parker instabilities on the one hand and a dynamo process on the other. A mechanical model for the Balbus-Hawley instability is presented and analysed quantitatively. Three-dimensional simulations are discussed, especially the resulting magnetic eld structure. Possibilities of reproducing the eld by an dynamo are investigated, especially its symmetry with respect to the midplane.
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