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Transport equation techniques for the deposition of auroral electrons

1976; American Geophysical Union; Volume: 81; Issue: 16 Linguagem: Inglês

10.1029/ja081i016p02755

2156-2202

D. J. Strickland, David Book, Timothy Coffey, J. A. Fedder,

Advanced Chemical Physics Studies

Journal of Geophysical Research (1896-1977)Volume 81, Issue 16 p. 2755-2764 Particles and Fields—Ionosphere Transport equation techniques for the deposition of auroral electrons D. J. Strickland, D. J. StricklandSearch for more papers by this authorD. L. Book, D. L. BookSearch for more papers by this authorT. P. Coffey, T. P. CoffeySearch for more papers by this authorJ. A. Fedder, J. A. FedderSearch for more papers by this author D. J. Strickland, D. J. StricklandSearch for more papers by this authorD. L. Book, D. L. BookSearch for more papers by this authorT. P. Coffey, T. P. CoffeySearch for more papers by this authorJ. A. Fedder, J. A. FedderSearch for more papers by this author First published: 1 June 1976 https://doi.org/10.1029/JA081i016p02755Citations: 162AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Abstract Auroral electron scattering and energy loss are calculated by using for the first time a multiangle equation of transfer at all energies. The results are compared with those obtained by 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 given between 10 eV and 20 keV, based on a measured auroral electron spectrum. These solutions are compared with similar results by Banks et al. (1974). The results agree above 3 keV but differ below that energy, a finding which is consistent with our comparisons of solutions of the equation of transfer and the Fokker-Planck equation. References Aarts, J. F. M., F. J. deHeer, Emission cross sections of the second positive group of nitrogen produced by electron impact, Chem. Phys. Lett., 4, 116, 1969. Banks, P. M., A. F. Nagy, Concerning the influence of elastic scattering upon photoelectron transport and escape, J. Geophys. Res., 75, 1902, 1970. Banks, P. M., C. R. Chappell, A. F. Nagy, A new model for the interaction of auroral electrons with the atmosphere: Spectral degradation, backscatter, optical emission, and ionization, J. Geophys. Res., 79, 1459, 1974. Berger, M. J., S. M. Seltzer, K. 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Green, Calculations of auroral intensities from electron impact, J. Geophys. Res., 72, 3967, 1967. Strickland, D. J., P. C. Kepple, Preliminary report on the transport and production of energetic electrons in aurorasNRL Memo. Rep. 2779Nav. Res. Lab., Wash., D. C., 1974. Walt, M., W. M. MacDonald, W. E. Francis, Penetration of auroral electrons into the atmosphere, Physics of the Magnetosphere R. L. Carovillano, J. F. McClays, H. R. Radoski, 534, D. Reidel, Dordrecht, Netherlands, 1967. Wedde, T., T. G. Strand, Scattering cross sections for 40 eV to 1 keV electrons colliding elastically with nitrogen and oxygen, J. Phys., 7, Sect. B, 1091, 1974. Citing Literature Volume81, Issue16Space Physics1 June 1976Pages 2755-2764 ReferencesRelatedInformation