Fig. 6

Ratio of the χ2 of the composite best fit of the entire time series to its minimum value vs. the parameter Q, i.e., the ratio of the facular area to the cool spot area in active regions. The horizontal dashed line indicates the 95% confidence level for χ2/. This does not put any significant constraint on the interval of acceptable Q values owing to the low signal-to-noise ratio of the data.
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