The coupling between the protonosphere and the normalFregion

Abstract

The proton distribution in the upper portion of the F2 region must follow a chemical equilibrium distribution up to a critical level, hc, which is determined by the condition λΛ = H2, where Λ is the mean free path for the scattering of protons by oxygen ions, A is the charge‐exchange mean free path for protons among oxygen atoms, and H is the scale height of atomic oxygen. Above this critical level, the distribution of protons is governed by diffusion. The number of protons in the whistler medium (that is, the protonosphere) is large enough, and the rate of diffusion of protons through oxygen ions slow enough, so that no large diurnal changes in whistler‐region ion concentrations can be expected. This is in agreement with observation. The weak coupling between the oxygen ions in the normal F2 region and the protons in the protonosphere lends support to the position that the protonosphere should be considered separately from the heavy ion region which constitutes the normal ionosphere; the protonosphere can be thought of, in large degree, as floating on top of the normal ionosphere.

He<sup>+</sup> dominance in the plasmasphere during geomagnetically disturbed periods: 1. Observational results

“…1). Direct photoionisation of neutral hydrogen is negligible, but during refilling of the flux tubes, the equilibrium reaction between O + and H + for the topside, (Hanson and Ortenburger, 1961) is maintained. In effect, this reaction means that the photoionisation of neutral oxygen is the ultimate source for both O + and H + .…”

Global morphology of night-time <i>Nm</i>F2 enhancements

“…The most important are: (1) plasma fluxes from the plasmasphere (Hanson and Ortenburger, 1961;Evans, 1965Evans, , 1975Titheridge, 1968;Jain and Williams, 1984;Förster and Jakowski, 1988;Jakowski et al, 1991;Jakowski and Förster, 1995;Mikhailov and Förster, 1999); (2) raising of the F2-layer to higher altitudes (where the recombination rate is smaller) by electric fields and thermospheric winds (Young et al, 1970;Standley and Williams, 1984;Hedin et al, 1991;Titheridge, 1995;Mikhailov et al, 2000a, b). Other less important processes are plasma transfer from conjugate points (Wickwar, 1974;Balan et al, 1994) and night-time ionization at the top of the ionosphere at high latitudes (Titheridge, 1968;Leitinger et al, 1982).…”

Mid-latitude electron density enhancement in the nocturnal topside ionosphere and its longitudinal inequalities.

“…The possibility of a field-aligned flow of thermal plasma from the nighttime protonosphere into the lower ionosphere was first pointed out by HANSON and ORTENBURGER (1961), and developed later by several workers (HANSON and PATTERSON, 1964;GEISLER and BOWHILL, 1965;NAGY et al, 1968;MOFFETT and MURPHY, 1973). PARK and BANKS (1974) have solved the continuity and momentum equations for H+ and O+ with appropriate boundary conditions, using various working models of the thermosphere taken from Tables B of BANKS and KoCKARTS (1973).…”