Power spectral density (PSD) distributions of GLS periodograms of 10,000 samples extracted from the run of ESPRESSO FWHM and RV measurements using a model with the GP and a Keplerian orbital model to search for the 3.15 d signal. The PSD distributions are extracted from the GLS periodograms at 3.15 d and the 1 d alias 1.46 d periods from simulated RV time series of the GP values plus white noise before (upper panel) and after (lower panel) subtracting the GP and injecting a planet signal in the simulated data. The observed PSD distributions (lower panel) are measured after subtracted the GP to the original RVs.