E. Mishin et al., On the electron distribution function in the F region and airglow enhancements during HF modification experiments, GEOPHYS R L, 27(18), 2000, pp. 2857-2860
The variation with height and plasma frequency of the distribution function
of ambient electrons (EDF) in the F region ionosphere during high-power, H
F radio wave modification experiments is discussed. It is shown that the de
viation of the EDF from a Maxwellian distribution (MD) in the high energy,
>2 eV, range may be quite significant (decreasing by a factor of 2 to 5) de
pending on the background parameters. As a result, the cooling and excitati
on rates are reduced with respect to a MD calculation. This, for example, c
an improve agreement of the model based on excitation by heated thermal ele
ctrons with the observations of 630.0 nm airglow during HF modification exp
eriments.