Summary of the GP best-fit model as obtained from the joint analysis of the HARPS+ESPRESSO RVs. Here, we show a portion of the HARPS time series, after removing the best-fit signal induced by planet b. The shaded area in gray represents the ±1σ confidence interval. Upper panel: best-fit model for the GP quasi-periodic kernel (orange line). Lower panel: same as above, but for the GP rotation kernel (blue line).