Signal frequency distribution in FTs of the 200-day light curves, including the constant-frequency sinusoidal component. The amplitudes of the sinusoidal components in the light curves were generated at two, three, four, and five times the σ levels (i.e., the average FT noise value of ~13.6 ppm). Only signals with amplitudes above the 4σ FT detection threshold were taken into account. For high simulated amplitudes, the corresponding FT signal frequencies are confined in a narrow ±0.02 μHz range (right panel). The range increases up to ±0.03 μHz for the low-amplitude signals. Left panel: enlarged ten times to account for the small number of signal detections above 4 σ.