Transport Techniques for Describing Scattering and Energy Deposition of Energetic Auroral Electrons.
Abstract
Auroral electron scattering and energy loss are calculated using for the first time a multi-angle equation of transfer at all energies. The results are compared with those obtained using a Fokker-Planck equation. Both equations have been solved in terms of their eigensolutions. The equation of transfer has also been solved by numerical integration. Fokker-Planck solutions agree well with equation-of-transfer solutions above 3 keV but deviate increasingly at lower energies. A comparison is made between the present Fokker-Planck results and those of M. Walt at 10 keV, giving good agreement. Energy deposition rates are also found to agree satisfactorily with those obtained previously. The accuracy of integration of the transfer equation is tested by comparing results obtained by the eigenvalue method and the direct integration method. Differences of less than 5% were found at all altitudes, energies and pitch angles. The predicted backscatter near the upper energy boundary' is sensitive to the boundary condition there. Backscatter results for various boundary conditions in energy show both this and the effects of the propagation of the boundary condition toward lower energies. Solutions to the equation of transfer are presented over the energy range from 10 ev to 40 keV and demonstrate the rapid rise in the flux below 100 ev, which is known to occur because of secondary electron production.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1975
- Accession Number
- ADA016584
Entities
People
- D. J. Strickland
- D. L. Book
- J. A. Fedder
- T. P. Coffey
Organizations
- United States Naval Research Laboratory