The Hot Electrons in and Above the Auroral Ionosphere: Observations and Physical Implications

  • Duncan A. Bryant
Part of the Nobel Foundation Symposia Published by Plenum book series (NOFS, volume 54)

Abstract

One of the great attractions of the aurora, rivalling even its dramatic appearance, is its continuing ability to mystify over the nature of its production. The mystery is nowhere more intriguing than where it surrounds the electrons that are the prime cause of the excitation. There is now widespread agreement that photon emission is controlled directly by the energy flux carried by electrons into the atmosphere (Omholt, 1959; Bryant et al., 1970; Lepine et al., 1979; McEwen et al., 1981) and recent measurements from a DMSP satellite (Fennell et al., 1981) give further reassurance on this point. Even so there is reason to believe that a straightforward correspondence between energy flux and emission may not hold in all circumstances (Stenbaek-Nielsen and Hallinan, 1979). The major uncertainty, though, is over the processes responsible for the electron streams that produce discrete forms such as auroral arcs and the more irregular and variable structures that occur during auroral breakup. In view of its overriding importance, the present discussion will concentrate on this issue, even though other important areas such as the electrons that produce pulsating aurora will remain untouched.

Keywords

Anisotropy Peaked 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Albert R. D., 1967, Nearly monoenergetic electron fluxes detected during a visible aurora, Phys. Rev. Letters, 18: 369.ADSCrossRefGoogle Scholar
  2. Arnoldy R. L., 1970, Rapid fluctuations of energetic auroral particles, J. Geophys. Res., 75: 228.ADSCrossRefGoogle Scholar
  3. Arnoldy R. L., 1981, Review of auroral particle precipitation, in: “Physics of Auroral Arc Formation”, Geophysical Monograph 25, American Geophysical Union, Washington, p56.Google Scholar
  4. Arnoldy R. L., Lewis P. B., and Isaacson P. 0., 1974, Field aligned auroral electron fluxes, J. Geophys. Res., 79: 4208.ADSCrossRefGoogle Scholar
  5. Barbosa D. D., 1977, Stability of shell distributions, Planet. Space Sci., 25: 981.ADSCrossRefGoogle Scholar
  6. Berko F. W., 1973, Distributions and characteristics of high-latitude field-aligned electron precipitation, J. Geophys. Res., 78: 1615.ADSCrossRefGoogle Scholar
  7. Bryant D. A., 1976, Local acceleration of auroral electrons, in: “The Scientific Satellite Programme during the International Magnetospheric Study”, D. Reidel. Publ. Co., Dordrecht, p413.CrossRefGoogle Scholar
  8. Bryant D. A., 1981, Rocket studies of particle structure associated with auroral arcs, in: “Physics of Auroral Arc Formation”, Geophysical Mograph 25, American Geophysical Union, Washington, p103.CrossRefGoogle Scholar
  9. Bryant, D. A., Courtier, G. M., Skovli, G., Lindalen, H. R., Aarsness, K., and Maseide, K., 1970, Electron density and Maseide, K., 1970, Electron density and electron flux in a glow aurora, J. Atmosph. Terr. Phys., 32: 1695.ADSCrossRefGoogle Scholar
  10. Bryant D. A., Hall D. S., and Lepine D. R., 1978, Electron acceleration in an array of auroral arcs, Planet. Space Sci., 26: 81.ADSCrossRefGoogle Scholar
  11. Bryant D. A., Hall D. S., Lepine D. R., and Mason R. W., 1977, Electrons and positive ions in an auroral arc, Nature, 266: 148.ADSCrossRefGoogle Scholar
  12. Burch J. L., Fields S. A., Hanson W. B., Heelis R. A., Hoffmann R. A., and Janetze R. W., 1976, Characteristics of auroral electron acceleration regions observed by atmospheric explorer C, J. Geophys. Res., 81: 2223.ADSCrossRefGoogle Scholar
  13. Chiu Y. T., Cornwall J. M., and Schulz M., 1981, Effects of auroral particle anisotropics and mirror forces on high-latitude electric fields, in: “Physics of Auroral Arc Formation”, Geophysical Monograph 25, American Geophysical Union, Washington, p234.CrossRefGoogle Scholar
  14. Eliasson L., Lundin R., and Sandahl I., 1980, Some results from the auroral particle experiment on board the Barium-Geos rocket, Proc. Vth ESA-PAC Symposium on European Rocket and Balloon Programmes and Related Research, ESA SP-152, p263.Google Scholar
  15. Evans D. S., 1967, A 10 cps periodicity iti the precipitation of auroral zone electrons, J. Geophys. Res., 72: 4281.ADSCrossRefGoogle Scholar
  16. Evans. D. S., 1968, The observation of a near monoenergetic flux of auroral electrons, J. Geophys. Res., 73: 2315.ADSCrossRefGoogle Scholar
  17. Evans D. S., 1971, Direct observations of temporal and spatial structure in auroral electrons, in: “The Radiating Atmosphere”, D. Riedel, Dordrecht, p267.Google Scholar
  18. Evans D. S., 1974, Precipitating electron fluxes formed by a magnetic field aligned potential difference, J. Geophys. Res., 79: 2853.ADSCrossRefGoogle Scholar
  19. Evans D. S., 1975, Evidence for the low altitude acceleration of auroral particles, in: “Physics of the Hot Plasma in the Magnetosphere”, Plenum Press, New York, p319.CrossRefGoogle Scholar
  20. Fennel1 J. F., Gorney D. J., and Mizera P. F., 1981, Auroral particle distribution functions and their relationship to inverted Vs and auroral arcs, in: “Physics of Auroral Arc Formation”, Geophysical Monograph 25, American Geophysical Union, Washington, p91.CrossRefGoogle Scholar
  21. Frank L. A., and Ackerson K. L., 1971, Observations of charged particle precipitation into the auroral zone, J. Geophys. Res., 76: 3612.ADSCrossRefGoogle Scholar
  22. Franklin R. N., Mackinley R. R., Edgley P. D., and Wall D. N., 1978, Non linear behaviour of a finite amplitude electron plasma wave, III The sideband instability, Proc. R. Soc. Lond., A360: 229.ADSCrossRefGoogle Scholar
  23. Gary S. P., Montgomery D., and Swift D. W., 1968, Particle acceleration by electrostatic waves with spatially varying phase velocities, J. Geophys. Res., 73: 7524.ADSCrossRefGoogle Scholar
  24. Gurnett D. A., and Frank L. A., 1977, A region of intense plasma wave turbulence on auroral field lines, J. Geophys. Res., 82: 1031.ADSCrossRefGoogle Scholar
  25. Hall D. S., 1980, The influence of energy diffusion on auroral particle distributions, Proc. Vth ESA-PAC Symposium on European Rocket and Balloon Programmes and Related Research, ESA SP-152, p285.Google Scholar
  26. Hall D. S., and Bryant D. A., 1974, Collimation of auroral particles by time-varying acceleration, Nature, 251: 402.ADSCrossRefGoogle Scholar
  27. Hoffmann R. A., and Evans D. S., 1968, Field-aligned electron bursts at high latitude observed by 0G0-4, J. Geophys. Res., 73: 6201.ADSCrossRefGoogle Scholar
  28. Hoffmann R. A., and Lin C. S., 1981, in: “Physics of Auroral Arc Formation”, Geophysical Monograph 25, American Geophysical Union, Washington, p80.CrossRefGoogle Scholar
  29. Hultqvist B., 1979, The hot ion component of the magnetospheric plasma and some relations to the electron component-observations and physical implications, Space Sci. Rev., 23: 581.ADSCrossRefGoogle Scholar
  30. Johnstone A. D., 1971, Correlation between electron and proton fluxes in post-breakup aurora, J. Geophys. Res., 76: 5259.ADSCrossRefGoogle Scholar
  31. Johnstone A. D., 1980, Wave-particle interactions in the high-latitude auroral ionosphere, Proc. Vth ESA-PAC Symposium on European Rocket and Balloon programmes and Related Research, ESA SP-152, p243.Google Scholar
  32. Johnstone A. D., Sojka, J. J., Gibbons, W., Madahar, B. K., and Woolliscroft, L. J. C., 1981, An intense wave/particle event in the auroral ionosphere, Geophys. Res. Letters, 8: 389.ADSCrossRefGoogle Scholar
  33. Jost R. J., Anderson H. R., and McGarity J. O., 1980, Electron energy distributions measured during electron beam/plasma interactions, Geophys. Res. Letters, 7: 509.ADSCrossRefGoogle Scholar
  34. Kaufmann R. L., and Ludlow G. R., 1981, Auroral electron beams: stability and acceleration, J. Geophys. Res., 86: 7577.ADSCrossRefGoogle Scholar
  35. Kaufmann R. L., Walker D. N., and Arnoldy R. L., 1976, Accelerations of auroral electrons by a parallel electric field, J. Geophys. Res., 81: 1673.ADSCrossRefGoogle Scholar
  36. Lauer Green, J., Gurnett D. A., and Hoffman R. A., 1979, A correlation between auroral kilometric radiation and inverted V electron precipitation, J. Geophys. Res., 84: 5216.Google Scholar
  37. Laval G., and Pellat R., 1970, Particle acceleration by electrostatic waves propagating in an inhomogeneous plasma, 75: 3255.Google Scholar
  38. Lepine D. R., Bryant D. A., and Hall, D. S., 1979, Proc. 7th annual meeting on upper atmosphere studies by optical methods, University of Tromso, p8.Google Scholar
  39. Lotko W., and Maggs J. E., 1979, Damping of electrostatic noise by warm auroral electrons, Planet. Space Sci., 27: 1491.ADSCrossRefGoogle Scholar
  40. Maehlum B. N., and Moestue H., 1973, High temporal and spatial resolution observations of low energy electrons by a mother- daughter rocket in the vicinity of two quiescent auroral arcs. Planet. Space Sci., 21: 1957.ADSCrossRefGoogle Scholar
  41. Maggs J. E., and Lotko W., 1981, Altitude dependent model of the auroral beam and beam generated electrostatic noise, J. Geophys. Res., 86: 3439.ADSCrossRefGoogle Scholar
  42. McEwen D. J., Yee E., Whalen B. A., and Yau A. W., 1981, Electron energy measurements in pulsating auroras, Can. J. Phys., 59: 1106.ADSCrossRefGoogle Scholar
  43. Mcllwain, C., 1960, Direct measurement of particles producing visible auroras, J. Geophys. Res., 65: 2727.ADSCrossRefGoogle Scholar
  44. Miller J. R., and Whalen B. A., 1976, Characteristics of auroral proton precipitation observed from sounding rockets, J. Geophys. Res., 81: 147.ADSCrossRefGoogle Scholar
  45. Mizera P. F., Fennell J. F., Croley Jr. D. R., and Gorney D. J., 1981, Charged particle distributions and electric field measurements from S3-3, J. Geophys. Res., 86: 7566.ADSCrossRefGoogle Scholar
  46. Mozer F. S., Carlson C. W., Hudson M. K., Torbert R. B., Parady B., Yatteau J., and Kelley M. C., 1977, Observations of paired electrostatic shocks in the polar magnetosphere, Phys. Rev. Letters, 38:292,ADSCrossRefGoogle Scholar
  47. Mozer F. S., Cattell C. A., Hudson M. K., Lysak R. L., Temerin M., and Torbert R. B., 1980, Satellite measurements and theories of low altitude auroral particle acceleration, Space Sci. Rev., 27: 155.ADSCrossRefGoogle Scholar
  48. O’Brien B. J., 1970, Consideration that the source of auroral energetic particles is not a parallel electrostatic field, Planet. Space Sci., 18: 1821.ADSCrossRefGoogle Scholar
  49. Omholt A., 1959, Studies on the excitation of aurora borealis II, Geophys. Publ., 21: 1.Google Scholar
  50. Pulliam D. M., Anderson H. R., Stamnes K., and Rees M. H., 1981, Auroral electron acceleration and atmospheric interactions; (1) rocket-borne observations and (2) scattering calculations, J. Geophys. Res., 86: 2397.ADSCrossRefGoogle Scholar
  51. Reasoner D. L., and Chappell C. R., 1973, Twin payload observations of incident and backscattered auroral electrons, J. Geophys. Res., 78: 2176.ADSCrossRefGoogle Scholar
  52. Sandahl I, Eliasson L., and Lundin R., 1980, Electron spectra over discrete auroras as measured by the Substorm-GEOS rockets Proc. Vth ESA-PAC Symposium on European Rocket and Balloon Programmes and Related Research, ESA SP-152, p257.Google Scholar
  53. Sharp R. D., Shelley E. G., Johnson R. G., and Ghielmetti A. G., 1980, Counterstreaming electron beams at altitudes of ∿ 1 RE over the auroral zone, J. Geophys. Res., 85: 92.ADSCrossRefGoogle Scholar
  54. Stenbaek-Nielsen H. C., and Hallinan T. J., 1979, Pulsating auroras: evidence for noncollisional thermalization of precipitating electrons, J. Geophys. Res., 84: 3257.ADSCrossRefGoogle Scholar
  55. Swift D. W., 1970, Particle acceleration by electrostatic waves, J. Geophys. Res., 75: 6324.ADSCrossRefGoogle Scholar
  56. Swift D. W., 1976, An equipotential model for auroral arcs, 2 Numerical solutions, J. Geophys. Res., 81: 3935.ADSCrossRefGoogle Scholar
  57. Temerin, M., Cattell C., Lysak R,, Hudson M., Torbert R. B., and Mozer F. S., 1981, The small-scale structure of electrostatic shocks, J. Geophys. Res., 86: 11, 278.Google Scholar
  58. Whalen B. A., and Daly P. W., 1979, Do field-aligned auroral particle distributions imply acceleration by quasi-static parallel electric fields? J. Geophys. Res., 84: 4175.ADSCrossRefGoogle Scholar
  59. Whalen B. A., and McDiarmid I. B., 1972, Observations of magnetic field aligned auroral electron precipitation, J. Geophys. Res. 77: 191.ADSCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1983

Authors and Affiliations

  • Duncan A. Bryant
    • 1
  1. 1.Rutherford Appleton LaboratoryChiltonUK

Personalised recommendations