Modelling p-Mode Interaction with a Spreading Sunspot Field
Abstract
Sunspots absorb and scatter incident p modes. The dominant mechanism is still uncertain. One possibility, mode conversion to slow magneto-acoustic waves, has been shown to yield results in agreement with observations for the f mode only. Absorption of p modes in simple vertical magnetic field models is too weak by an order of magnitude or more. Here we report on numerical calculations of p modes encountering a simple sunspot model with field which spreads with height. It is found that p-mode absorption is greatly enhanced by field spread, to a level consistent with observations, and it appears that it occurs preferentially in the outer regions of the spot, in line with recent results from acoustic holography.
- Publication:
-
Solar Physics
- Pub Date:
- March 2000
- DOI:
- 10.1023/A:1005213002513
- Bibcode:
- 2000SoPh..192..395C
- Keywords:
-
- Magnetic Field;
- Numerical Calculation;
- Recent Result;
- Field Model;
- Outer Region