Is Jupiter's ionosphere a significant plasma source for its magnetosphere?

Abstract

A semikinetic model was used to study the steady state, collisionless, polar wind outflow from the Jovian polar caps. H+ escape fluxes and energies were calculated for a range of conditions, including several values of the ambient electron temperature, different hot electron populations, and both with and without the effects of the centrifugal force. The calculations indicate that if hot electron populations exist over the Jovian polar caps, as they do on earth, polar wind escape fluxes of the order of 108 cm−2 s−1 are possible. When integrated over the polar cap area, escape fluxes of this order of magnitude imply an ionospheric source strength of 2×1028 ions/s, which is comparable to the present estimate of the total magnetospheric plasma source population. Therefore, the ionosphere may play an important role in populating the Jovian magnetosphere, specifically the “hidden,” low energy, light ion component of the population.