Composition and energy spectrum variations of auroral ions

We have detected H+,O+, and He++ ions with E/q up to 20 keV/charge in a hydrogen aurora over Churchill, Manitoba, during the flight of a Javelin sounding rocket on February 11, 1975, We observed several examples of different types of ion events. One type consisted of bursts of H+ and O+ ions which arrived simultaneously at all energies within the range of the E/q analyzer. These events were apparently of local origin (distance <1R/sub E/ from the earth) and had a large component of O+ ions (O+/H+approximately-greater-than30%). A second type of event consisted of bursts of enhanced H+ counting rates but no O+ ions. The dispersion in time of the energy spectrum was consistent with an injection and acceleration site located at about 20 R/sub E/ from the earth. An enhancement of the He++ counting rates was associated with these events, but the He++ data are of limited statistical significance. A third type of event, consisting of short bursts of H+ ions with wide energy spreads, was observed in association with an event in which the energy of the H+ ions showed time dispersion. We interpret these short H+ bursts as due to ions trapped in traveling waves generated by an explosive injection of plasma in the earth's magnetotail