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arXiv · 1501.05597

Application of Mutual Information Methods in Time-Distance Helioseismology

Dustin Keys·Shukur Kholikov·Alexei Pevtsov
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Abstract

We apply a new technique, the mutual information (MI) from information theory, to time-distance helioseismology, and demonstrate that it can successfully reproduce several classic results based on the widely used cross-covariance method. MI quantifies the deviation of two random variables from complete independence, and represents a more general method for detecting dependencies in time series than the cross-covariance function, which only detects linear relationships. We provide a brief description of the MI-based technique and discuss the results of the application of MI to derive the solar differential rotation profile, a travel-time deviation map for a sunspot and a time-distance diagram from quiet Sun measurements.

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Dustin Keys, Shukur Kholikov, Alexei Pevtsov. 2015-06-09. Application of Mutual Information Methods in Time-Distance Helioseismology. https://doi.org/10.1007/s11207-015-0650-y

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