Three-dimensional ray propagation in a toy sunspot
Abstract
In time-distance helioseismology wave travel times are measured from the cross-correlation between Doppler velocities recorded at any two locations on the solar surface. However, one of the main uncertainties associated with such measurements is how to interpret observations made in regions of strong magnetic field. Isolating the effects of wave anisotropies produced by the magnetic field from those thought to be associated with temperature and flow perturbations has proved to be quite complex and has yet to yield results when extracting acoustic travel times from the cross-correlation function. One possible way to decouple these effects is by using a three-dimensional toy sunspot with a surrounding stratified field-free Model S atmosphere to model the magneto-acoustic ray propagation and produce artificial travel time perturbation maps that directly account for wave speed anisotropies produced by the magnetic field.
- Publication:
-
Journal of Physics Conference Series
- Pub Date:
- October 2008
- DOI:
- 10.1088/1742-6596/118/1/012037
- Bibcode:
- 2008JPhCS.118a2037M