Turbulent Dynamos and Magnetic Helicity
نویسنده
چکیده
It is shown that the turbulent dynamo -e ect converts magnetic helicity from the turbulent eld to the mean eld when the turbulence is electromagnetic while the magnetic helicity of the meaneld is transported across space when the turbulence is electrostatic or due to the electron diamagnetic e ect. In all cases, however, the dynamo e ect strictly conserves the total helicity except for a battery e ect which vanishes in the limit of magnetohydrodynamics. Implications for astrophysical situations, especially for the solar dynamo, are discussed. PACS numbers: 52.30.Jb, 96.60.Hv, 91.25.Cw Typeset using REVTEX
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