Plasma sounding at the upper hybrid frequency

Details Plasma sounding at the upper hybrid frequency Plasma sounding at the upper hybrid frequency

Jun 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000jgr...10513103d&link_type=abstract

Journal of Geophysical Research, Volume 105, Issue A6, p. 13103-13118

Computer Science

Sound

2

Electromagnetics: Numerical Methods, Electromagnetics: Plasmas, Electromagnetics: Wave Propagation, Electromagnetics: Instrumentation And Techniques

Scientific paper

A sounder measures the density of plasmas in various parts of the solar system. The sounder emits wave pulses into the ambient plasma and listens to the response. Intensity peaks in the wave response are typically related to two mechanisms. One is provided by waves that are reflected off plasma inhomogeneities and propagate back to the emitting antenna, where they are then detected. The second is provided by waves propagating with the same group velocity as that of the receiving antenna. In the second case the waves stay close to the antenna and thus yield a long-lasting response. Response peaks to sounding at the upper hybrid (UH) frequency have, in most cases, been related to reflected waves. In this work we examine if accompanying waves can give rise to the UH response peak. We examine quantitatively how the plasma response to sounding at the UH frequency depends on the plasma density, on the electron temperature, and on the emission amplitude. For the first two parameters this is done by solving the linear dispersion relation. The well-known property of the UH waves to change from having a zero group velocity to propagating waves, depending on how the electron density compares to the electron cyclotron frequency, is applied to Alouette sounder data. It is discussed how the change in the group velocity may affect the spectral profile of the UH resonance. We present results from numerical particle in cell (PIC) simulations which show that in the case of nonpropagating UH waves, energy can be coupled into the plasma even though the vanishing group velocity of the UH waves should not allow this. The PIC simulations and sounder data from the Alouette mission show that in the case of propagating UH waves the response duration to sounding may be used to determine the electron temperature. Emission amplitudes that are typical for plasma sounders are also shown to suppress the generation of certain electron cyclotron harmonic waves.

Affiliated with

Also associated with

No associations

Rating

Plasma sounding at the upper hybrid frequency does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Plasma sounding at the upper hybrid frequency, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Plasma sounding at the upper hybrid frequency will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1350801