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07:58
Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
Seismic probes of solar interior magnetic structure
Shravan Hanasoge1, Aaron Birch, Laurent Gizon
1Department of Geosciences, Princeton University, New Jersey 08544, USA. hanasoge@princeton.edu
Physical Review Letters
|September 26, 2012
Summary
Accurately imaging Sun
Area of Science:
- Solar physics
- Helioseismology
- Magnetohydrodynamics
Background:
- Sun spots are key features of solar magnetoconvection.
- Imaging their subsurface structure is crucial for understanding solar dynamics.
- Current methods often oversimplify wave propagation in magnetic fields.
Purpose of the Study:
- To develop a more accurate method for seismic imaging of Sun spot subsurface structures.
- To account for wave propagation complexities in magnetized solar plasma.
- To improve the parametrization of magnetic interior properties.
Main Methods:
- Utilized partial-differential-equation-constrained optimization.
- Developed a model incorporating seven distinct wave speeds.
- Accounted for anisotropic magnetic effects on wave propagation.
Main Results:
- Identified seven wave speeds characterizing helioseismic propagation.
- Demonstrated that ignoring magnetic anisotropies leads to significant inversion errors.
- Showed that translation invariance is lost when anisotropies are neglected.
Conclusions:
- Accurate seismic imaging of solar magnetoconvection requires accounting for wave anisotropies.
- The new parametrization enables more precise subsurface structure determination.
- This approach promises improved understanding of magnetic phenomena on the Sun.
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