Top panel: Best sine-fit periods derived from the radial velocity curves of the Hα emission line in the OSIRIS spectra, as a function of the double-Gaussian separation used in the velocity extraction. The shaded horizontal band indicates the periods derived from the light curves. Error bars represent 1σ uncertainties. Bottom panel: Periods corresponding to the highest peaks in the GLS (blue circles) and AOV (orange squares) periodograms derived from the quiescent FORS2 Hα radial velocity curves, as a function of the Gaussian separation used to extract the velocities. The period search was restricted to the range 0.068−0.25 d. The lower shaded horizontal band marks the periods observed in the photometric light curves, while the upper band corresponds to twice these values.