Drift loss cone instability in the ring current and plasma sheet

  • K. G. Bhatia
  • G. S. Lakhina


The drift loss cone instability, propagating nearly transverse to the ambient magnetic field, is studied in the ring current plasma taking into account the relative driftU between electrons and protons due to density gradients. The growth rates attain maxima and then decrease as the wave number parallel to the magnetic fieldk II increases. The peak values of the growth rates, maximised with respect tok II, are enhanced by the increase in number density, electron temperature and loss cone index, and by the decrease in βt, the ratio of the proton thermal pressure to magnetic field pressure. The unstable frequencies fall in the range of 5 to 30Ωp with the growth rate γ ≥Ωp. In the ring current region betweenL=4 and 5, the instability will generate a strong turbulence in the frequency range between 5–500 Hz which can produce fluctuating electric fields 0. 5–5 mV/m and magnetic field 0.8–80mγ. This instability can also occur on the auroral field lines, which connect to the region of intense earthward plasma flow in the distant magnetotail and produce a broad band electrostatic noise.


Drift loss cone instability ring current plasma sheet broad band electrostatic noise magnetosphere 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Anderson R A and Gurnett D A 1973J. Geophys. Res. 78 4756CrossRefGoogle Scholar
  2. Arefev V I 1970Sov. Phys. Tech. Phys. 14 1487Google Scholar
  3. Bernstein W, Hultqvist B and Borg H 1974Planet. Space Sci. 22 767CrossRefGoogle Scholar
  4. Bhatia K G and Lakhina G S 1977Planet. Space Sci. 25 833CrossRefGoogle Scholar
  5. Cornwall J M, Coroniti F V and Thorne R M 1970J. Geophys. Res. 75 4699CrossRefGoogle Scholar
  6. Cornwall J M 1973 Effect of instabilities on the ring current. Presented toIAGA Symposium on magnetospheric configuration, Kyoto, JapanGoogle Scholar
  7. Coroniti F V, Fredricks R W and White R 1972J. Geophys. Res. 77 6243CrossRefGoogle Scholar
  8. Cuperman S and Gomberoff L 1977J. Plasma Phys. 18 391CrossRefGoogle Scholar
  9. Davidson R C, Gladd N T, Wu C S and Huba J D 1977Phys. Fluids 20 301CrossRefGoogle Scholar
  10. Fried B D and Conte S D 1961The plasma dispersion function (New York: Academic Press)Google Scholar
  11. Gurnett D A and Frank L A 1977J. Geophys. Res. 82 1031CrossRefGoogle Scholar
  12. Gurnett D A, Frank L A and Lepping R P 1976J. Geophys. Res. 81 6059Google Scholar
  13. Huba J D, Gladd N T and Papadopoulos K 1978J. Geophys. Res. 83 5214CrossRefGoogle Scholar
  14. Krall N A 1968Advances in Plasma Phys. (eds A Simon and W B Thompson (New York: Interscience)1 153Google Scholar
  15. Lakhina G S 1976Planet. Space Sci. 24 609CrossRefGoogle Scholar
  16. Lakhina G S and Sen A 1973Nucl. Fusion 13 913Google Scholar
  17. Liewer P C and Davidson R C 1977Nucl. Fusion 17 85Google Scholar
  18. Lemons D S and Gary S P 1977J. Geophys. Res. 82 2337CrossRefGoogle Scholar
  19. Mizera P F 1974J. Geophys. Res. 79 581CrossRefGoogle Scholar
  20. Post R F and Rosenbluth M N 1966Phys. Fluids 9 730CrossRefGoogle Scholar
  21. Williams D J and Lyons L R 1974J. Geophys. Res. 79 4791CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 1980

Authors and Affiliations

  • K. G. Bhatia
    • 1
  • G. S. Lakhina
    • 1
  1. 1.Indian Institute of GeomagnetismColaba, Bombay

Personalised recommendations