The theory of the amplitude modulation of finite amplitude kinetic Alfvén waves in a medium beta plasma is re-examined and extended. The modulational and filamentational instabilities as well as associated localized structures in magnetic field and plasma density are investigated. The relevance of our investigation to coherent nonlinear structures in the ionospheric plasma is pointed out.
Shukla, P. K., Bingham, R., & Dendy, R. O. (1998). Amplitude modulation of kinetic Alfvén waves and the formation of nonlinear structures. Physics Letters A, 239(6), 369-372. https://doi.org/10.1016/S0375-9601(98)00070-X