Using the cold plasma dispersion relation and whistler mode waves to quantify the antenna sheath impedance of the Van Allen Probes EFW instrument

The excitation of the whistler mode waves propagating obliquely to the constant and uniform magnetic field in a warm and inhomogeneous plasma in the presence of an inhomogeneous beam of suprathermal electrons is studied. The full dispersion relation including electromagnetic effects is derived. In the electrostatic limit the expression for the growth rate is given. It is found that the inhomogeneities in both beam and plasma number densities affect the growth rates of the instabilities.

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Van Allen Probes observations of unusually low frequency whistler mode waves observed in association with moderate magnetic storms: Statistical study

Geophysical Research Letters ◽

10.1002/2015gl065565 ◽

2015 ◽

Vol 42 (18) ◽

pp. 7273-7281 ◽

Cited By ~ 15

Author(s):

C. A. Cattell ◽

A. W. Breneman ◽

S. A. Thaller ◽

J. R. Wygant ◽

C. A. Kletzing ◽

...

Keyword(s):

Statistical Study ◽

Low Frequency ◽

Magnetic Storms ◽

Whistler Mode ◽

Van Allen Probes ◽

Whistler Mode Waves

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Dispersion relation of electromagnetic ion cyclotron waves using Cluster observations

Annales Geophysicae ◽

10.5194/angeo-31-1437-2013 ◽

2013 ◽

Vol 31 (8) ◽

pp. 1437-1446 ◽

Cited By ~ 7

Author(s):

I. P. Pakhotin ◽

S. N. Walker ◽

Y. Y. Shprits ◽

M. A. Balikhin

Keyword(s):

Dispersion Relation ◽

Wave Vector ◽

Cold Plasma ◽

High Plasma ◽

Minimum Variance ◽

Ion Cyclotron Waves ◽

Hot Plasma ◽

Ion Cyclotron ◽

Electromagnetic Ion Cyclotron Waves ◽

Plasma Dispersion

Abstract. Multi-point wave observations on Cluster spacecraft are used to infer the dispersion relation of electromagnetic ion cyclotron (EMIC) waves. In this study we use a phase differencing method and observations from STAFF and WHISPER during a well-studied event of 30 March 2002. The phase differencing method requires the knowledge of the direction of the wave vector, which was obtained using minimum variance analysis. Wave vector amplitudes were calculated for a number of frequencies to infer the dispersion relation experimentally. The obtained dispersion relation is largely consistent with the cold plasma dispersion relation. The presented method allows inferring the dispersion relation experimentally. It can be also used in the future to analyse the hot plasma dispersion relation of waves near the local gyrofrequency that can occur under high plasma beta conditions.

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Improved derivation of the modified BGK collision term and applications to the Hall effect and cold plasma dispersion relation

Journal of Plasma Physics ◽

10.1017/s0022377800001264 ◽

1983 ◽

Vol 30 (3) ◽

pp. 371-387 ◽

Cited By ~ 3

Author(s):

M. Nagata

Keyword(s):

Dispersion Relation ◽

Hall Effect ◽

Cyclotron Resonance ◽

Velocity Vector ◽

Cold Plasma ◽

Collision Frequency ◽

Collision Term ◽

Macroscopic Equation ◽

Plasma Dispersion ◽

The Magnetic Field

We improve our previously derived addition to the BGK collision term, and express it in a simple form. The collision frequency for scattering now depends anisotropically on the velocity vector. We also apply the improved macroscopic equation of momentum flow to the Hall effect, the cold plasma dispersion relation and the cyclotron resonance. The Hall coefficient which is constant in the case of the BGK collision term now depends on the magnetic field. It is also shown that, compared with the almost symmetric classical curves of cyclotron resonance, the new curves are considerably asymmetric and their half-widths are about 3/2 times the classical ones.

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