NonMaxwellian velocity distribution functions and incoherent scattering of radar waves in the auroral ionosphere
Abstract
For studies of the highlatitude ionosphere it is important to calculate the effect of convection electric fields on the velocity distribution functions. At an altitude where the plasma is weakly ionized, the appropriate Boltzmann equation is solved in the spatial homogeneous case. The characteristics of the ion nonequilibrium steady state reached for large electric fields are discussed from the macroscopic point of view. From the microscopic point of view, it is shown that the Grad expansion fails to converge rapidly for large electric fields. Generalized polynomial expansions are developed for different models of ionneutral interactions. The consequences of these nonMaxwellian ion distribution functions on radar waves are presented, and erroneous interpretations of measurements are discussed.
 Publication:

Journal of Atmospheric and Terrestrial Physics
 Pub Date:
 July 1984
 DOI:
 10.1016/00219169(84)900771
 Bibcode:
 1984JATP...46..601H
 Keywords:

 Auroral Zones;
 Incoherent Scatter Radar;
 Radar Scattering;
 Velocity Distribution;
 Wave Propagation;
 Distribution Functions;
 Molecular Ions;
 Nitric Oxide;
 Oxygen Ions;
 Positive Ions;
 Propagation Velocity;
 Space Plasmas;
 Communications and Radar