GLS power of the whole S_MWO time series (solid blue line) and the whole time series without the longest period (dashed blue line). We also show the GLS power of the window function (red line), of the S_MWO data of the TIGRE telescope and the Mount Wilson program data alone (cyan and green line, respectively), and of the S_{Ca IRT} of the three Ca II IRT lines (yellow, orange, and magenta with increasing central wavelength).