Lomb-Scargle periodograms of the 37 last days of HARPS RV data of CoRoT-7. The dotted line shows the level of the mean uncertainty in RV measurements. a) The main peak in the raw data is owing to the rotational period of the star (~23 d.). b) After the harmonic filtering of the data, the highest peak of the residuals corresponds to the CoRoT-7c period. c) The residuals of the simultaneous fit of the activity and one Keplerian for CoRoT-7c show two peaks, the highest at the CoRoT-7b period and the other at its one-day alias. d) No significant periods remains above the level of the noise after the simultaneous fit of the activity and of two Keplerians for the possible companions.