Test‐Particle Simulations of Linear and Nonlinear Interactions Between a 2‐D Whistler‐Mode Wave Packet and Radiation Belt Electrons

Abstract. We show that nonlinear wave trapping plays a significant role in both the generation of whistler-mode chorus emissions and the acceleration of radiation belt electrons to relativistic energies. We have performed particle simulations that successfully reproduce the generation of chorus emissions with rising tones. During this generation process we find that a fraction of resonant electrons are energized very efficiently by special forms of nonlinear wave trapping called relativistic turning acceleration (RTA) and ultra-relativistic acceleration (URA). Particle energization by nonlinear wave trapping is a universal acceleration mechanism that can be effective in space and cosmic plasmas that contain a magnetic mirror geometry.

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Hot plasma theory of whistler mode wave packet propagation along a non-uniform magnetic field

Journal of Plasma Physics ◽

10.1017/s0022377800004669 ◽

1969 ◽

Vol 3 (4) ◽

pp. 611-631 ◽

Cited By ~ 4

Author(s):

M. J. Houghton

Keyword(s):

Magnetic Field ◽

Wave Packet ◽

Uniform Magnetic Field ◽

Particle Distribution ◽

Whistler Mode ◽

Mode Wave ◽

Whistler Mode Wave ◽

History Of ◽

Smallness Parameter ◽

Image Position

We discuss the propagation of wave packets of the formin an infinite uniform plasma, where G(z, t) is a slowly varying function of space z and time t. One can very simply derive the equation of change of G(z, t) for the stable or unstable case. The terms in the equation are of physical interest and clearly define the limitations of linear theory. We then investigate the problem of whistler mode wave propagation in a collisionless Vlasov plasma in a given non-uniform magnetic field. We choose the electric field to be of a W.K.B. form and the particle distribution to be isotropic. We can express the perturbation in the particle distribution in terms of an integration along the zero-order par tide orbits (an integration overtime). These orbits can be found correct to a term linear in a smallness parameter ε (when ε equals zero we arrive back at a uniform magnetic field). The charge and current density due to the perturbation are related through Maxwell's equations to the electric and magnetic field of the wave in the usual self consistent Boltzmann—Vlasov description. We show that the contribution to the current arises from recent events in the history of a given particle because of the finite temperature of the plasma. This result leads to an expansion of slowly varying parameters which in turn gives rise to the equation governing the motion of the wave packet.

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Radiation from an electron beam in magnetized plasma: excitation of a whistler mode wave packet by interacting, higher-frequency, electrostatic-wave eigenmodes

Plasma Physics and Controlled Fusion ◽

10.1088/1361-6587/aa941b ◽

2017 ◽

Vol 59 (12) ◽

pp. 124006 ◽

Cited By ~ 1

Author(s):

N Brenning ◽

I Axnäs ◽

M Koepke ◽

M A Raadu ◽

E Tennfors

Keyword(s):

Electron Beam ◽

Wave Packet ◽

Magnetized Plasma ◽

Electrostatic Wave ◽

Whistler Mode ◽

Mode Wave ◽

Whistler Mode Wave ◽

Plasma Excitation

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Interactions between magnetosonic waves and radiation belt electrons: Comparisons of quasi-linear calculations with test particle simulations

Geophysical Research Letters ◽

10.1002/2014gl060461 ◽

2014 ◽

Vol 41 (14) ◽

pp. 4828-4834 ◽

Cited By ~ 50

Author(s):

Jinxing Li ◽

Binbin Ni ◽

Lun Xie ◽

Zuyin Pu ◽

Jacob Bortnik ◽

...

Keyword(s):

Test Particle ◽

Radiation Belt ◽

Particle Simulations ◽

Radiation Belt Electrons

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Importance of the landau resonance of a whistler-mode wave packet centered at half the gyrofrequency

Journal of Atmospheric and Terrestrial Physics ◽

10.1016/0021-9169(75)90165-8 ◽

1975 ◽

Vol 37 (8) ◽

pp. 1171-1172

Author(s):

Nakd Kishore Vyas ◽

Anath Chandra Das

Keyword(s):

Wave Packet ◽

Whistler Mode ◽

Mode Wave ◽

Whistler Mode Wave

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Nonlinear interactions between relativistic radiation belt electrons and oblique whistler mode waves

Nonlinear Processes in Geophysics ◽

10.5194/npg-17-599-2010 ◽

2010 ◽

Vol 17 (5) ◽

pp. 599-604 ◽

Cited By ~ 61

Author(s):

X. Tao ◽

J. Bortnik

Keyword(s):

Radiation Belt ◽

Nonlinear Interactions ◽

Whistler Mode ◽

Nonlinear Phase ◽

Resonant Interactions ◽

Induced Motion ◽

Radiation Belt Electrons ◽

Whistler Mode Waves ◽

Adiabatic Motion ◽

Wave Induced

Abstract. Resonant interactions between relativistic charged particles and oblique whistler mode waves are explored in this work, and it is shown that nonlinear phase trapping could happen in a gyrophase averaged sense, consistent with previous studies of interactions between nonrelativistic electrons and oblique whistler mode waves. A dimensionless parameter χ is derived to represent the ratio of wave-induced motion to the adiabatic motion of the particle. We show that phase trapping is likely to occur when the wave-induced motion dominates the adiabatic motion, which is caused mainly by the background fields. A mapping of probable regions of nonlinear interactions is shown based on the parameter χ. We show that the nonlinear interactions might be important near the equatorial plane for even moderate wave amplitude, and the latitudinal range for nonlinear interactions to occur is largest for electrons with local pitch angles around 50 degrees, consistent with previous findings. The results are important for understanding the nonlinear dynamics of relativistic radiation belt electrons and the generation of chorus waves.

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