Imaging the Sun’s Near-surface Flows Using Mode-coupling Analysis

  title={Imaging the Sun’s Near-surface Flows Using Mode-coupling Analysis},
  author={Prasad Mani and Chris S. Hanson and Shravan M. Hanasoge},
  journal={The Astrophysical Journal},
The technique of normal-mode coupling is a powerful tool with which to seismically image non-axisymmetric phenomena in the Sun. Here we apply mode coupling in the Cartesian approximation to probe steady, near-surface flows in the Sun. Using Doppler cubes obtained from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, we perform inversions on mode-coupling measurements to show that the resulting divergence and radial vorticity maps at supergranular length scales (∼30… 

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