Sectoral power spectra for the synthetic radial vorticity data for the complete solar surface (full Sun, left panel), including the observational window function (pre-treatment, central panel), and after processing (post-treatment, right panel). Cyan arrows show the peaks at ±(1 year)⁻¹ = ±31.7 nHz. Blue arrows show the leakage of |m| = 1 into m = 0 once the window function is applied. These leakages coincide with the annual variation. After treatment, the annual variation and its leakage disappears, leaving the m = 1 r-modes and associated leakage. The green arrows highlight the effects the window has on m = 1 power.