Open AccessSolitary waves and weak double layers in a two‐electron temperature auroral plasma
Author(s) -
Berthomier M.,
Pottelette R.,
Malingre M.
Publication year - 1998
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/97ja00338
Subject(s) - amplitude , physics , plasma , electron temperature , ion , atomic physics , electron , population , range (aeronautics) , electron density , excited state , plasma parameters , computational physics , materials science , quantum mechanics , demography , sociology , composite material
We show that the main characteristics of ion acoustic solitary waves and weak double layers observed by the Swedish satellite Viking can be well reproduced assuming the presence of two electron components in the auroral plasma. The characteristics of the ion acoustic solitons excited in such a plasma are derived with the help of the Sagdeev potential. The results show that the interactions between the hot and the cold electron component in the presence of a finite ion temperature produce rarefactions of the localized density. Such nonlinear structures exist in a more extended range of plasma parameters than the one previously studied in the small amplitude limit case using the Korteweg‐de‐Vries equation. We find that the density of the cold population must be always smaller than the hot one, while the hot to cold temperature ratio must be greater than ∼ 10. The characteristics of these structures are quite different from those obtained in the small amplitude limit case and better reproduce the Viking observations in terms of their velocity, width, and amplitude scales.