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Fig. 21.

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Variations in Hα flux (not absorption) measured during the 2016 data period, together with contemporaneous full-disk Hα images and (adjacent smaller circles) photospheric magnetograms, at selected labeled dates of local Hα-flux maxima or minima. Daily Hα flux averages are large red dots, individual exposures are small and black. The full-disk images were acquired by GONG instruments operated by NISP/NSO/AURA/NSF with contributions from NOAA (Global Oscillation Network Group 2024).

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