Table 1.

Mount Wilson classification rules, number of each AR, and total number of joint patches or pixels per Mount Wilson class used in this paper when using the STARA masks.

Class Classification rule Number of AR Number of patches
α A single dominant spot 50 13,358
β A pair of dominant spots of opposite polarity 192 75,463
βγ A β sunspot where a single north-south polarity 130 95,631
inversion line cannot divide the two polarities
βγδ A βγ sunspot where umbrae of opposite polarity are together in a single penumbra 52 66,195

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