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The combination of high resolution, spatial coverage, and continuity of photospheric Doppler and other data from HMI has allowed us to embark on a program of systematic exploration of solar subsurface flows and thermal structure variations using the technique of ring-diagram analysis on an unprecedented scale. There are two ring-diagrams pipelines, as described in [1]. In this paper we discuss the synoptic pipeline execution and describe the data being processed and produced.
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Bogart et al. (2011) studied this question.
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