Results from magnetospheric Gedanken experiments using the LFM

The Lyon–Fedder–Mobarry global magnetospheric model couples a magnetohydrodynamic simulation of the solar wind magnetosphere interaction to a 2D simulation of the ionosphere. Event studies driven by solar wind observations made by WIND and ACE have proved the utility and accuracy of the model. Recently we have begun conducting a series of Gedanken experiments using the LFM as our testbed. By creating idealized solar wind conditions we are able to explore a portion of solar wind parameter space and determine the response of the coupled magnetosphere–ionosphere system. This paper will summarize results from two of these thought experiments. In the first experiment we used an abrupt transition from northward to southward interplanetary magnetic field to examine the development of polar cap convection in ionosphere and how the dayside magnetopause erodes under south-ward IMF. Next we use solar wind conditions which contained ultra low frequency (ULF) waves in the plasma density and show that it is possible to drive ULF waves in the magnetosphere with this direct driving from the solar wind. Using these computer assisted thought experiments we are able to move beyond the typical cartoon picture of the magnetosphere and probe its fundamental physics.