Examples of light curves generated using celerite varying the process parameters: damping timescale τ (panel a), and the variability amplitude $\widehat{\sigma }$ (panel c). In the right panels, the retrieved periodograms (computed as discussed in Appendix A) as well as the theoretical expected PSD (dashed lines) are shown. The time series ($\widehat{F}$) are centred at zero and have arbitrary units. The parameter σ and power (P) should be considered in terms of the same dimensional scale as $\widehat{F}$, with P having units of the square of the units of $\widehat{F}$.