Professor Robert Lysak

This group is creating models of the propagation of magnetohydrodynamics (MHD) waves through the magnetospheres of Earth and Jupiter. This effort includes three separate but related projects.

• The researchers have developed a global three-dimensional MHD code to describe the interaction of MHD waves with the collisional ionosphere. This model includes the effects of Hall conductivity in the ionosphere as well as the finite magnetic zenith angle (the angle between the magnetic field direction and the vertical). The existing models have used dipolar coordinates to more accurately model the geometry of the magnetosphere; however, this leaves gaps in the equatorial and polar regions. The researchers are devloping a model in spherical coordinates that should address these gaps.
• The researchers have also developed a more localized code that can describe the role of MHD waves in the development of parallel electric fields in the auroral zone. This model includes parallel electric fields due to electron pressure and inertia as well as a phenomenological model of Landau damping. The model includes the nonlinearities due to convection and the Lorentz force to understand the filamentation of currents in Jupiter's magnetosphere. 
• The researchers have developed a model of Alfven waves generated by Jupiter's moon Io, which acts as a generator for these Alfven waves and produces its own auroral signature. This model can follow the evolution of these waves and potentially explain the structure of the auroral tail that extends beyond the magnetic footprint of Jupiter.
• The most recent project studies the polar cap region of Jupiter, which exhibits an unusual plasma environment with high magnetic fields and very low densities. The researchers are studying the density structure using a code based on Liouville's theorem as well as wave codes similar to those described above to model Alfven, electromagnetic ion cyclotron, and whistler mode waves in this region.