Analysis of the HARPS radial velocities. Periodogram for RV time series where a linear drift was subtracted is shown in the top panel. We can see a peak at 3.7 days corresponding to the period of the planet, and another at 1.36 days corresponding to its alias. Both peaks have a false alarm probability ≪ 1%. The lower panel is the periodogram for RVs where a linear drift and Keplerian (for the first planet) were subtracted; the highest peak at 5.9 days has a false alarm probability of 20.8%.