Example of the ratio in a solar-like model with respect to the normalised variable t = τ/τ₀ (the surface is located on the right-hand side and the centre is made visible by a cut on the axis). In the above plot, we have chosen a typical solar pulsation frequency ω = 2π × 3000 μHz. The wave propagates in the blue shaded region (0.01 < t < 0.99) below the horizontal dashed line (ω_c = ω) while being damped in the red shaded area. The dotted line near the surface has been added for the sake of comparison and represents the symmetric counterpart to the curve near the centre. It overlaps with the actual curve down to the ionisation region.