Evolution of three parameters extracted from the DEM analysis: DEM-weighted temperature, DEM slope and total Emission Measure (EM). These time series are averaged over the black contour displayed in Fig. 1. We included the 171 light curve from Fig. 2 for reference. All these quantities are normalised to the standard deviation and offset on the y-axis. If there is a detection, we display the corresponding period detected, the Fourier power and the associated random occurrence probability. The grey bar indicates the SST observations duration. An animation of this figure is available online.