Orbit-resolved space–time diagram of τ for a region near the density wave resonance resulting from the integration shown in Fig. C.1 with β = 1.20 for times t ≳ 20 000 ORB. The nearly horizontal pattern that becomes increasingly pronounced with increasing r > r_L represents the density wave. The smaller scale structures are overstable waves that are perturbed by the satellite resonance, causing the “wiggles” in their appearance, in contrast to the waves displayed in Fig. 7. The green dashed line is the expected phase speed ω_I ∕k of (unperturbed) overstable waves with λ = 300 m obtained from Fig. 8. A profile of τ is drawn forthe time indicated by the arrow, showing how the amplitude of overstable waves is reduced in approaching the resonance from smaller radii. Visible as well are the first wave cycles of the density wave.