Fig. 2.
From: Field-line resonance structures in Mercury’s multi-ion magnetosphere
The wave spectra of the perturbed electric field: (a) the radial component of B x and (b) the azimuthal component of B y . The horizontal axis is the direction of inhomogeneity, X, and the vertical axis is a normalized frequency that ranges from 0 to 1. The white solid, dashed, and dashed-dotted lines in (a) are Ωii(A), Ω L , and Ω, R , respectively, and yellow dashed lines in (b) represent Ωii(A) . Here, there are two IIH resonances in 0.5 < Ωii−1 < 1 and 0.25 < Ωii−2 < 0.5, and one Alfvén resonance in Ω A < 0.25. The open circles mark the point chosen for time histories.