Left panels, top panel: CARMENES VIS RVs (blue dots) together with a Keplerian model combined with a simple-harmonic oscillator (SHO) model shown in orange. The Keplerian-only curve is shown with a light blue color. Second panel: RV residuals after subtracting the combined Keplerian + simple-harmonic oscillator model from the original data. Third and bottom panels: GLS periodograms of the original data (light blue line) and of the RV residuals (orange) as a function of frequency and period. The model accounts for the two strongest peaks at 16.6 d and 24.4 d. Right panels: CARMENES Hα data compared to a simple harmonic oscillator (SHO) model (see Sect. 5.2) and the residuals (top two panels), as well as the periodogram as a function of frequency and period (lower two panels). Top panel: best fit model is shown in orange, the 1σ uncertainty in blue. The periodograms show the data in light blue and the residuals in orange.