Comparison between the real and alias signals in the RV data of WASP-121 corrected for the planet signal (red shadow) and in the simulated data (black). Top panels: 0.89-day signal, bottom panels: 1.13-day signal. These plots correspond to one realization of noise out of 100 different trials. Real signals are shown in black (panels A3 and B2), yearly aliases (± 0.0027 days⁻¹) in green (panels A3 and B2), daily aliases (±1, ± 1.0027 and ± 1.0056 days⁻¹) in blue (panels A1, A4, B1, and B4), and 2-day aliases (± 2.0027 and ± 2.0055 days⁻¹) in purple (panels A2, A5, B3, and B5). Arrows at the top of each peak show the phase of each signal for the real (red) and the simulated data (black).