Matched-filter flare detection illustrated for Flare 1. (a) Two-dimensional matched-filter S/N map as a function of trial peak time t₀ and template FWHM. (b) One-dimensional detection statistic obtained by maximizing the S/N over the FWHM at each t₀ and then smoothing in time; the horizontal dashed line marks the adopted detection threshold (S/N = 10), and the star marks the detected peak. (c) Hα light curve around the detected event (points) together with the best-matching flare template (curve) corresponding to the peak in panel (b). This event occurs during a planetary transit. However, no explicit transit subtraction is applied in Hα, since stellar variability dominates at these wavelengths and cadences.