Dispersive Alfven Waves in Space and Laboratory Plasmas

Dartmouth College, Hanover NH

Investigators

Abstract

The investigators will study structural and dynamical features of small-scale, dispersive Alfven waves in magnetized, strongly inhomogeneous, low-beta laboratory and space plasmas. Dispersive Alfven waves generated at the equatorial plane of the magnetosphere may transport electromagnetic power into the ionosphere and can be responsible for small-scale, intense electric fields and currents in the topside auroral ionosphere and in discrete auroral arcs. The study will used a model based on the reduced two-fluid magnetohydrodynamic (MHD) kinetic equations which incorporate effects of finite electron and ion masses, temperatures, and kinetic effects of the finite ion Larmor radious in the fluid description of ultra-low-frequency electromagnetic waves in a magnetized plasma. To understand the range of applicability of the reduced MHD description of dispersive Alfven waves, the investigators will verify the physical model and its numerical implementation on a large set of well-controlled, comprehensive experimental data. In particular, the effort involves testing the results of theoretical models with laboratory plasma experiments performed on the Large Plasma Device at UCLA. Results of the study will be applied to further the capability to interpret intense fields, currents and particle fluxes measured in the auroral zone on rockets and satellites as well as to advance understanding of laboratory plasma experiments.