Best fit for Si III λ4553 (left) and He I λ5876 (right) lines resulting from mode identification with the FPF method for a single radial mode configuration with i = 60°, υ_e sin i = 100 km s⁻¹, f = 5.25 d⁻¹, and υ_amp = 21 kms⁻¹ as inputs. The FPF method fits a model (red line) to the observational (blue line) zero-point (top panel), amplitude (middle panel), and phase (bottom panel) profiles for each detected pulsation frequency mode. The statistical uncertainty range of the observations and the model are shown by the red and green shaded areas, respectively.