1305.0875 (M. Svanda et al.)

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

M. Svanda, Th. Roudier, M. Rieutord, R. Burston, L. Gizon

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.

View original: http://arxiv.org/abs/1305.0875