Abstract


  SEISMOLOGY OF MAGNETIC FIELDS IN THE SOLAR INTERIOR

  S. Hanasoge, Tata Institute of Fundamental Research, hanasoge@gmail.com

Sunspots are prominent manifestations of solar magnetoconvection, and imaging their subsurface
structure is an outstanding problem of wide physical importance. Travel times of seismic waves that
propagate through these structures are typically used as inputs to inversions. Despite the presence of
strongly anisotropic magnetic waveguides, these measurements have always been interpreted in terms
of changes to isotropic wavespeeds and flows. Seven different wave speeds fully characterize
helioseismic wave propagation: the isotropic sound speed, a Doppler-shifting flow-advection velocity,
and an anisotropic magnetic velocity. The structure of magnetic media is sensed by magnetoacoustic
slow and fast modes and Alfve ́n waves, each of which propagates at a different wave speed. Here we
discuss methodology that can self-consistently account for all these aspects, rendering plausible the
accurate seismic imaging of magnetoconvection in the interior.