HR: 13:55h
AN: SM53C-02    [Abstracts]
TI: Plasma Dynamics in the Vicinity of a Cusp-Like Magnetic Configuration
AU: * Adamson, E T
EM: eric_adamson@hotmail.com
AF: Geophysical Institute, University of Alaska, Fairbanks, Fairbanks, AK 99775 United States
AU: Otto, A
EM: ao@why.gi.alaska.edu
AF: Geophysical Institute, University of Alaska, Fairbanks, Fairbanks, AK 99775 United States
AB: The magnetospheric cusps are an important structural element of the Earth's magnetosphere. Magnetic flux from the magnetospheric boundaries converges into the cusps and the magnetic field in the vicinity of the cusps rotates by 360 degrees. The magnetic field and plasma flow configuration allows for magnetic reconnection and Kelvin Helmholtz instabilities in the vicinity of the cusps. In addition plasma flow can become turbulent due to boundary layer separation as a result of the plasma flow over the cusp indentation. However, there are very few models based on first principles and with good numerical resolution which address the cusp physics. Here we will present results based on two and three dimensional MHD simulations with an initial condition which includes a cusp-like magnetic field indentation. The initial conditions particularly address cases with various magnetic field orientations relative to the magnetosheath plasma flow. The results consider a variation of the velocity on the magnetosheath side, the influence of viscosity on the the flow structure in and adjacent to the cusp, and the location of turbulent onset. Consideration will also be given to the possibility of standing waves within the cusp which is a topic of recent (contraversial) discussion in the field.
DE: 7835 Magnetic reconnection
DE: 7843 Numerical simulation studies
DE: 2724 Magnetopause, cusp, and boundary layers
DE: 2753 Numerical modeling
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting