Structure of a given mode solution for the lowest frequency mode. Top left: relative Alfvén speed as a function of transverse and longitudinal coordinates, x and y, respectively, for the parameters values of χ = 0.1, ζ = 160, L = 252 Mm, a = 5 Mm, y₀ = 6 Mm, and Δy = 1 Mm. The horizontal dashed lines indicate x = ±a. Top right: real part of the fundamental transverse eigenmode, . The subsequent panels show some of the individual basic modes that contribute to the full eigenmode. The relative amplitudes of those basic modes relative to are given.