Table 3.

The solar features identification criteria that have been adopted in this work, and the parameters employed to identify them, from the respective data set. Intensitygrams and magnetograms are shortened to Int and Mag, respectively.

Feature Data type Detection criterium Description
Sunspots Int Th ss = 〈I〉 − f ss where f ss = 15
Pores Int Th pores = 〈Iregion − (f p × σ I,SMin) where f p = 7, and σ I,SMin = 1.5
Umbra, penumbra Int Th up = 〈Iss − σ ss where 〈Iss is the mean of sunspot groups and σ ss is the standard deviation of sunspot group. Umbra and penumbra are defined after the detection of sunspots. Sunspot pixels with values below the threshold are classified as umbra, while the remaining sunspot pixels are classified as penumbra.
Faculae Mag Th mr = 〈B〉 ± (f mr × σ B,SMin) where f mr = 2 and σ B,SMin = 2.4
Faculae are magnetic regions, except sunspots, located within active region boundaries
Network Mag Th mr = 〈B〉 ± (f mr × σ B,SMin) where f mr = 2 and σ B,SMin = 2.4
Network are magnetic regions located outside active regions.

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