Physics
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010agufmsm33a1880s&link_type=abstract
American Geophysical Union, Fall Meeting 2010, abstract #SM33A-1880
Physics
[2431] Ionosphere / Ionosphere/Magnetosphere Interactions, [2704] Magnetospheric Physics / Auroral Phenomena, [2752] Magnetospheric Physics / Mhd Waves And Instabilities, [2753] Magnetospheric Physics / Numerical Modeling
Scientific paper
Results from a numerical study of the nonlinear interaction between ultra-low-frequency (ULF) shear Alfvén waves, slow MHD waves, and the magnetospheric plasma are presented. The goal of this study is to investigate effects of multiple heavy ion species (in particular, O+ and O2+) on formation and dynamics of density and electromagnetic structures in the low-altitude auroral magnetosphere and the ionosphere. Interest to this problem is motivated by many geophysical phenomena including ion outflow, density cavities, electron acceleration, and strong, small-scale magnetic field aligned currents observed with ground-based radars and satellites in a close vicinity of discrete auroral arcs. The basic hypothesis investigated in this study is that these phenomena are produced by intense ULF electromagnetic waves standing/propagating along geomagnetic field lines and interacting with the ionosphere and the low-altitude magnetosphere. This study is based on a novel multi-fluid MHD model describing ULF MHD waves in the cold, low-altitude magnetospheric plasma. The model includes nonlinear coupling between shear and slow MHD modes (parallel ion dynamics for several ion species), as well as the effects of active ionospheric response (feedback) on structure and amplitude of magnetic field-aligned currents carried by the waves and interacting with the ionosphere. Under the favorable conditions these interactions can lead to the so-called feedback instability. Numerical simulations of multi-fluid MHD model have been performed in the dipole magnetic field geometry with realistic parameters of the ambient plasma. Simulations show that the ionospheric feedback instability is one of the major contributors to the formation of intense electromagnetic and plasma structures in the ionosphere and low-altitude magnetosphere at high latitudes.
No associations
LandOfFree
Effect of heavy ions on nonlinear coupling between the magnetosphere and the ionosphere in the auroral zone does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Effect of heavy ions on nonlinear coupling between the magnetosphere and the ionosphere in the auroral zone, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effect of heavy ions on nonlinear coupling between the magnetosphere and the ionosphere in the auroral zone will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1470590