Lomb-Scargle periodogram of the HARPS (HAM) ΔT measurements. The solid blue line shows the power as a function of period, while the horizontal red, green, and blue dashed lines mark the 1%, 0.1%, and 0.01% analytical false alarm probability thresholds respectively. There are no significant peaks around the planets’ periods. There is a forest of statistically significant peaks between 13 and 20 days which shows a sign of potential differential rotation.