OBSERVATIONS OF SUPRATHERMAL IONS IN ASSOCIATION WITH SLAMS

We present observations of 1.4-20 keV ions in association with short large amplitude magnetic structures (SLAMS) using high time resolution AMPTE/UKS data near the quasi-parallel Earth's bow shock. The observations show a strong temporal gradient in the suprathermal ion pressure as the convecting SLAMS passes. We discuss these observations in the context of recent simulation studies which predict that SLAMS are the result of the steepening of a ULF wave as it passes through an energetic particle pressure gradient and present a simple picture illustrating the relationship between this spatial gradient and the observed temporal one.