Alias analysis of raw time series: (a) RV, (b) FWHM, (c) S-index. We focus on the aliases of the 48.6 d signal. (d) The window function reveals four prominent peaks at 215 d (upward teal triangle), 365 d (blue circle), 475 d (downward red triangle), and 635 d (green square). The relevant aliases in data periodograms are plotted with dashed lines of a corresponding colour and marker.