Nonlinear standing shear Alfvén waves in the Earth's magnetosphere

• Author(s) / Creator(s)

  • Tikhonchuk, V. T.
  • Frycz, P.
  • Samson, J. C.
  • Rankin, Robert

• We present theory and numerical simulations of strong nonlinear effects in standing shear Alfven waves (SAWs) in the Earth's magnetosphere, which is modeled as a finite size box with straight magnetic lines and (partially) reflecting boundaries. In a low beta plasma it is shown that the ponderomotive force can lead to large-amplitude SAW spatial harmonic generation due to nonlinear coupling between the SAW and a slow magnetosonic wave. The nonlinear coupling leads to secularly growing frequency shifts, and in the case of driven systems, nonlinear dephasing can lead to saturation of the driven wave fields. The results are discussed in the context of their possible relevance to the theory of standing ionospheric cavity wave modes and field line resonances in the high-latitude magnetosphere.

• Date created

  1994

• Subjects / Keywords

  • Cavity
  • Modulational Instability
  • Field Line Resonances
  • Plasma
  • Evolution
  • Magnetic-Field
  • Auroral Arcs
  • Driven

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/R33F4M29G

• License

  © 1994 American Geophysical Union. This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.