There has been
a long standing dispute on the origin of accelerated
particles observed at the Earth's magnetic cusps. Observations show the
presence of an energetic particle population in the vicinity of these
cusps, however there are various hypotheses on the origin and the
acceleration mechanism. While some believe that these particle are
indeed accelerated locally in the cusp magnetic field geometry another
hypothesis assumes that these particle are accelerated at the
quasi-parallel bow shock of the magnetosphere and are only found at the
cusp if this bow shock region is magnetically connected to the cusp.
Similarly there are several hypotheses on a possible local acceleration
mechanism with the dominant idea of acceleration by a turbulent wave
field. The presentation summarizes observations and arguments
accelerated particle populations in the cusps and will discuss first
results of simulations of particle dynamics in a cusp geometry.