COMPARISON OF SOLAR SURFACE FLOWS INFERRED FROM TIME-DISTANCE HELIOSEISMOLOGY AND COHERENT STRUCTURE TRACKING USING HMI/SDO OBSERVATIONS
Abstrakt
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 two-dimensional horizontal flows on the solar surface, whereas the time-distance inversions estimate the full three-dimensional velocity flows in the shallow near-surface layers.
Both techniques use Helioseismic and Magnetic Imager observations as 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 three-dimensional time-distance inversion.