Figure 5: Relation between the S index and the stellar brightness variation.
From: Observational evidence for enhanced magnetic activity of superflare stars
The brightness variation amplitude measurements are from Notsu et al.31 for the same 11 stars as in Fig. 4. A strong correlation is seen, which agrees well with the strong correlation seen between the residual flux in the core of the infrared Ca II 8542 line and the brightness variation amplitude by Notsu et al.31 The error bars are calculated using the relation in Supplementary Fig. 2. The error bars in the figure represent a single standard deviation.
