Concentration of Toroidal Magnetic Field in the Solar Tachocline by η-Quenching
Abstract
We show that if the turbulent magnetic diffusivity used in solar dynamos is assumed to be ``quenched'' by increasing toroidal fields, much larger amplitude and more concentrated toroidal fields can be induced by differential rotation from an assumed poloidal field than if there is no quenching. This amplification and concentration mechanism is weakened and bounded by jXB feedbacks on the differential rotation. Nevertheless, it is strong enough to contribute to the creation of ~100 kG toroidal fields near the base of the convection zone, perhaps in conjunction with the ``exploding flux tube'' process. Such high fields are necessary for sunspots to occur in low solar latitudes.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2005
- DOI:
- 10.1086/431929
- arXiv:
- arXiv:astro-ph/0504003
- Bibcode:
- 2005ApJ...630..615G
- Keywords:
-
- Sun: Interior;
- Sun: Magnetic Fields;
- Sun: Rotation;
- Astrophysics
- E-Print:
- 8 pages, 6 figures, added references, corrected typos, accepted by ApJ