SAMPEX measurements of heavy ions trapped in the magnetosphere

Abstract
New observations of >15 MeV/nuc trapped heavy ions with Z greater than or equal to 2 have been made by the SAMPEX spacecraft in low polar orbit. The composition of these ions, which are located primarily around L = 2, is dominated by He, N, O, and Ne. The N, O, and Ne ions are apparently trapped ''anomalous cosmic rays,'' while the origin of the trapped He flux is presently uncertain. These ions can affect the rate of single-event upsets (SEUs) in spacecraft hardware.