Relevant solutions (3 and 4) of the local dispersion relation for the real (left) and imaginary (right) part of the vertical wavenumber k_z corresponding to the cases P (B₀ = 17.4G) and P-b (B₀ = 52.3). The MHD solutions are indicated by solid lines in both panels. Left panel: the reflection heights for the fast component are indicated by black and blue vertical dotted lines for P and P-b, respectively. The equipartition heights are shown with a gray and light blue vertical dot-dashed lines for P and P-b, respectively. Right panel: we also show Solutions 3 and 4 for the ambipolar cases with dashed lines. The points where the ambipolar and MHD Solution 3 (fast modes) diverge are indicated by the markers for both P (black marker) and P-b (blue marker) cases.