Light ion concentrations and fluxes in the polar regions during magnetically quiet times

Ion concentrations, flow velocities, and fluxes, measured by the ion mass spectrometer on the Isis 2 satellite for periods around the solstices and equinoxes of 1971 and 1972, have been used in a study of the polar wind morphology during magnetically quiet times. The results confirm the major tenets of polar wind theories; namely, that an upward flow of both H+ and He+ ions exists at all times over the entire polar region; H+ fluxes are of the order of 108 ions/cm2 s in both summer and winter polar regions. O+ is the dominant ion specie at 1400‐km altitude in regions of strong H+ flows, and H+ is depleted over the entire region where the polar wind flows. H+ fluxes tend to be lower in winter than in summer, whereas He+ fluxes are a factor of 10 higher in winter and tend to follow the neutral helium concentration near the F2 maximum. The latter agree well with model calculations of flux in the winter but lie above the model values by a factor of 2 in the summer. H+ fluxes also agree well with ion flow models.