Dynamo action by internal waves in accretion disks
Journal Article
·
· Astrophysical Journal; (USA)
- Texas Univ., Austin (USA) California Univ., La Jolla (USA)
An analysis is conducted of the ability of low frequency, slightly nonaxisymmetric waves in thin accretion disks to drive an alpha-Omega dynamo in a disk. The asymmetry in the wave distribution which creates a nonzero helicity follows from the fact that the fundamental waves all have a positive angular momentum flux. As a result there will be a large-scale magnetic field driven by an alpha-Omega dynamo. It is also likely that small-scale fields, driven by higher-order wave modes, will contribute significantly to the local value of B(r)B(phi). It is argued that the magnetic field saturates when its pressure is comparable to the thermal pressure, and a crude model of the nonlinear of transfer of power to small-scale turbulence is presented. 42 refs.
- OSTI ID:
- 6104990
- Journal Information:
- Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 365; ISSN ASJOA; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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