Alfvén mode on a single iso-surface
In this section:
The Alfvén mode is decoupled from the magneto-acoustic modes in a magnetic slab.
The perturbations are in the homogeneous direction (y-direction), meaning that each magnetic iso-surface within the slab can oscillate independently without perturbing the plasma density or pressure.
Consequently, the parameters (and asymmetry) of the plasma external to the slab do not affect the propagation of this mode.
Red lines – magnetic field lines
Grey surface – slab boundaries
White arrows – velocity direction field