Measuring solar structure variations from helioseismic and photometric observations
There has been some discussion at this meeting of small changes in frequencies and frequency splittings observed during the solar cycle. Previous observations of frequency changes at the level of 10−4 have been convincingly confirmed by several observations presented at this meeting (Jefferies et al. 1990; Libbrecht and Woodard 1990; Pallé et al. 1990). It has been noted that solar photometric (differential and absolute) observations are of comparable accuracy and show similar solar cycle variations. I will summarize here how the latest photometric and helioseismic data may be accounted for by changes in the the convection zone during a solar cycle. Some of these data and this model have been further described elsewhere (Kuhn 1989; Goode and Kuhn 1990).
KeywordsSolar Cycle Convection Zone Magnetic Cycle Solar Luminosity Flux Perturbation
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