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Fig. A.2


Regression slope of the dependence of photometric brightness variation on HK emission variation, plotted vs. mean chromospheric activity calculated for α = 0 (original AS coverages given by Eq. (1), solid curve), α = 0.5 (increased AS coverages, dotted curve), α = − 0.5 (decreased AS coverages, dashed curve). The calculations are performed for homogeneous distribution of active regions.

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