Large Scale Turbulent
نویسنده
چکیده
There is a class of dynamos where the eld is caused by a velocity eld which, in turn, is driven by the generated magnetic eld. Numerical three-dimensional simulations of this type of process are reviewed. This process is here discussed in connection with accretion discs, but we point out that similar mechanisms have also been suggested in the context of solar and galactic dynamos. The underlying instability is diierent in each case: Balbus-Hawley and Parker instabilities in accretion discs, magnetostrophic wave instabilities in the sun, and Parker instabilities in galaxies, but probably also in the sun.
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