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The disk dynamo

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The simplest αω dynamo in a thin disk is analysed. It the antisymmetric helicity function α(z) (wherez is a coordinate perpendicular to the disk plane) is smooth and limited, then the conditions for generating a magnetic field and the symmetry of the resulting solutions depend only on the form of α at the segment (0,h) — whereh is the half-thickness of the disk — and the value of the dimensionless dynamo numberD. When α(z) does not change its sign at this segment andD>D c (the critical dynamo number), the excitation of non-oscillating even (quadrupole) and oscillating odd (dipole) fields are possible. When α(z) changes its sign at the segment indicated, non-oscillating odd magnetic fields can also be excited.

The old exact solutions of the disk αω dynamo are studied and new ones are found. The results can be of importance when applied to the problem of the generation of a magnetic field in galactic and turbulent disks appearing around some X-ray sources.

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Ruzmaikin, A.A., Sokoloff, D.D., Turchaninoff, V.I. et al. The disk dynamo. Astrophys Space Sci 66, 369–384 (1979). https://doi.org/10.1007/BF00650011

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  • Magnetic Field
  • Exact Solution
  • Thin Disk
  • Disk Plane
  • Dynamo Number