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arXiv · 1001.4508

Seismic Constraints on Interior Solar Convection

S. M. Hanasoge·T. L. Duvall Jr.·M. L. DeRosa
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Abstract

We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by analyzing simulations of waves propagating through a velocity snapshot of global solar convection via methods of time-distance helioseismology. Applying identical analysis techniques to observations of the Sun, we are able to bound from above the magnitudes of solar convective cells as a function of spatial convective scale. We find that convection at a depth of $r/R_\odot = 0.95$ with spatial extent $\ell <20$, where $\ell$ is the spherical harmonic degree, comprise weak flow systems, on the order of 15 m/s or less. Convective features deeper than $r/R_\odot = 0.95$ are more difficult to image due to the rapidly decreasing sensitivity of helioseismic waves.

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S. M. Hanasoge, T. L. Duvall Jr., M. L. DeRosa. 2010-01-25. Seismic Constraints on Interior Solar Convection. https://doi.org/10.1088/2041-8205%2F712%2F1%2Fl98

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