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arXiv · 1305.0875

Comparison of solar surface flows inferred from time--distance helioseismology and coherent structure tracking using HMI/SDO observations

M. Svanda·Th. Roudier·M. Rieutord·R. Burston·L. Gizon
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Abstract

We compare measurements of horizontal flows on the surface of the Sun using helioseismic time--distance inversions and coherent structure tracking of solar granules. Tracking provides 2D horizontal flows on the solar surface, whereas the time--distance inversions estimate the full 3-D velocity flows in the shallow near-surface layers. Both techniques use HMI observations as an input. We find good correlations between the various measurements resulting from the two techniques. Further, we find a good agreement between these measurements and the time-averaged Doppler line-of-sight velocity, and also perform sanity checks on the vertical flow that resulted from the 3-D time--distance inversion.

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M. Svanda, Th. Roudier, M. Rieutord, R. Burston, L. Gizon. 2013-05-04. Comparison of solar surface flows inferred from time--distance helioseismology and coherent structure tracking using HMI/SDO observations. https://doi.org/10.1088/0004-637x/771/1/32

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