Radar observations of non-thermal plasmas at different aspect angles

Data are presented from the EISCAT CP-3-E experiment which show the presence of non-thermal plasma over a range of latitudes. The O+ ion-velocity distribution function is almost toroidal when the electric field reaches values of 125 mV m−1. The ion temperature derived from such data assuming a Maxwe...

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Bibliographic Details
Published in:Advances in Space Research
Main Authors: Winser, K.J., Lockwood, Mike, Jones, G.O.L., Suvanto, K.
Format: Article in Journal/Newspaper
Language:unknown
Published: 1989
Subjects:
Online Access:https://centaur.reading.ac.uk/38873/
https://doi.org/10.1016/0273-1177(89)90347-5
Description
Summary:Data are presented from the EISCAT CP-3-E experiment which show the presence of non-thermal plasma over a range of latitudes. The O+ ion-velocity distribution function is almost toroidal when the electric field reaches values of 125 mV m−1. The ion temperature derived from such data assuming a Maxwellian distribution function will overestimate the true ion temperature when the observing angle is large with respect to the magnetic field, and underestimate the temperature when the aspect angle is small. When the expressions for the distribution function are extended to include mixed ion composition, an improvement is sometimes found in fitting the observed data, and estimates of the composition can be made. Such an analysis suggests that N2+ can occasionally form a significant part of the total ion density in a narrow height region centred at 275 km.