GLS periodogram of GJ 806 for different detrended time series. The black line (top panel) denotes the GLS of pEW(Hα); the blue and the green line (second panel from top) denote respectively the bluest and the middle line of the Ca II IRT; the violet line (third panel from top) denotes the TiO index; and the red line (bottom panel) denotes the window function. In all panels, the dashed horizontal line marks the FAP of 0.01, above which signals are rated as significant.