Energetic oxygen ions of ionospheric origin observed in the cusp

On 8/27/96 from 8 to 10:36 UT the POLAR satellite crossed the dayside cusp and observed very energetic ionospheric Oless than or equal to +2 ions whic h had a magnetic moment spectrum, M(E) that followed a power law. Later at 14:45 to 15:30 UT the satellite passed through the ring current at 15-16 ML T where the Oless than or equal to +2 ions again had a M(E) power law form but with a spectral amplitude that was two orders of magnitude lower. Durin g this period from 8 to 16 UT there were no magnetic storms as D-st had an average value of similar to -5 nT. The comparison of the fluxes at constant M means that the energetic ions in the cusp cannot have a source in the ri ng current. Arguments are given that the comparison of these sequential mea surements of M(E) are valid and that a new mechanism is needed for producin g these energetic ionospheric ions observed in the cusp.