Space Science Center
There are two sources for the plasma in the Earth's magnetosphere: the solar wind and the ionosphere. The solar wind is predominantly protons, with a small percentage of alpha particles and high charge state heavy ions, while the ionosphere provides low charge state ions, primarily hydrogen and O+. Although the protons are common to both sources, the heavy ions can be used to differentiate the sources, and to better understand the acceleration mechanisms and transport paths that bring the ions into the Earth's magnetotail and inner magnetosphere. We are involved in a number of studies using Van Allen Probes, Cluster, MMS, FAST, and Arase data to better understand how the two sources are accelerated and transported within the magnetosphere, and how the ion composition impacts the magnetospheric dynamics.