Comparison of the observed pulsation frequencies and the best-fitting model. Top: Lomb-Scargle periodogram of the complete light curve (light grey) with the prewhitened pulsation frequencies with S/N ≥ 4.0 (full red lines) and dark red arrows marking the frequencies with S/N ≥ 5.6. The best-fitting asymptotic g-mode patterns (dashed lines) for the r modes (left) and the prograde dipole modes (right) are also shown. The parts of the theoretical patterns that cannot be resolved properly (where the spacing Δν between consecutive frequencies is less than twice the frequency resolution ν_res are shown by the grey dashed lines. Bottom: the residuals (black) of the modelled observed frequencies, and the differences (grey) between the remaining observed frequencies and the closest model frequencies. G modes with 4.0 ≤ S/N <  5.6 that are not shown in the bottom panel, lie outside of the plotted range.