Articles | Volume 14, issue 1
Ann. Geophys., 14, 27–32, 1996
https://doi.org/10.1007/s00585-996-0027-5
Ann. Geophys., 14, 27–32, 1996
https://doi.org/10.1007/s00585-996-0027-5

  31 Jan 1996

31 Jan 1996

Excitation of VLF quasi-electrostatic oscillations in the ionospheric plasma

B. Lundin, C. Krafft, G. Matthieussent, F. Jiricek, J. Shmilauer, and P. Triska B. Lundin et al.

Abstract. A numerical solution of the dispersion equation for electromagnetic waves in a hot magnetized collisionless plasma has shown that, in a current-free ionospheric plasma, the distortion of the electron distribution function reproducing the downward flow of a thermal electron component and the compensating upward flow of the suprathermal electrons, which are responsible for the resulting heat flux, can destabilize quasi-electrostatic ion sound waves. The numerical analysis, performed with ion densities and electron temperature taken from the data recorded by the Interkosmos-24 (IK-24, Aktivny) satellite, is compared with a VLF spectrum registered at the same time on board. This spectrum shows a wide frequency band emission below the local ion plasma frequency. The direction of the electron heat flux inherent to the assumed model of VLF emission generation is discussed