Lomb-Scargle periodogram (LSP) in the 50–450 μHz frequency range (left panel) and the 450–1100 μHz frequency range (right panel), where signal is found. The reconstructed LSP based on the extracted harmonic oscillations given in Table 1 (indicated by red vertical segments) is shown upside down. The curve shifted downward is the LSP of the residual (i.e., noise) after subtracting all the frequencies of Table 1 from the observed light curve.