Satellite observations of an ionospheric acceleration mechanism

Abstract

A satellite‐borne energetic ion mass spectrometer experiment has detected fluxes of O + and H + ions flowing up out of the ionosphere in the auroral and polar regions. The observed ions have energies in the keV range, narrow pitch‐angle distributions aligned along the magnetic field direction and peak flux intensities of the order of 10 8 (cm²‐sec‐sterad‐keV) −1 . The observations were made at altitudes between 5000 and 8000 km on both the day and nightsides of the earth.