Physics Department Seminar University of Alaska Fairbanks

J O U R N A L    C L U B


Analysis of Magnetic Cavities in the Vicinity of a Cusp-like Magnetic Configuration

Eric Adamson
Physics Dept. and Geophysical Institute

The Magnetospheric cusps are a key feature of the Earth's magnetosphere, as they offer the solar wind its most direct entry point to the 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 allow for magnetic reconnection and Kelvin Helmholtz instabilities in the vicinity. In addition, plasma flow can become turbulent due to boundary layer separation as a result of the plasma flow over the cusp indentation. The cusps also exhibit regions of significantly depressed magnetic field accompanied by enhanced density and pressure. These regions have been referred to as cusp diamagnetic cavities(CDC) or the stagnant exterior cusp(SEC). Many questions remain with regard to these cavities. In order to investigate the cusp region, we have implemented a high resolution local three dimensional MHD simulation with an initial configuration representing a cusp-like magnetic field. I will discuss the construction of such an initial configuration. I will also present results which address general cusp characteristics and their dependence on the Interplanetary Magnetic Field(IMF) as well as an analysis of the cusp diamagnetic cavities.

Friday, 2 February 2007
Globe Room, Elvey Building
3:45 PM