Resonant acceleration of charged particles in the presence of random fluctuations

Abstract. New evidence reveals that the charged particles can be energized locally in the magnetospheric cusp. The power spectral density of the cusp magnetic fluctuations shows increases by up to four orders of magnitude in comparison to an adjacent region. Large fluctuations of the cusp electric fields have been observed with an amplitude of up to 350 mV/m. The measured left-hand polarization of the cusp electric field at ion gyro-frequencies indicates that the cyclotron resonant acceleration mechanism is working in this region. The cyclotron resonant acceleration can energize ions from keV to MeV in seconds.

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Non-resonant acceleration of charged particles driven by the associated effects of the radiation reaction

Journal of Plasma Physics ◽

10.1017/s0022377820001105 ◽

2020 ◽

Vol 86 (5) ◽

Author(s):

F. Russman ◽

I. Almansa ◽

E. Peter ◽

S. Marini ◽

F. B. Rizzato

Keyword(s):

High Frequency ◽

Charged Particles ◽

Localization Length ◽

Hamiltonian Formalism ◽

Radiation Reaction ◽

Speed Of Light ◽

Wave Localization ◽

Particle Speed ◽

Resonant Acceleration ◽

Localization Region

In the present analysis, we study effects of the radiation reaction (RR) on the dynamics of charged particles submitted to the action of localized longitudinal high-frequency carriers travelling at the speed of light. As the wave's crests and troughs keep overtaking particles, dissipative RR forces tend to drag particles alongside the wave in an effort to reduce the relative wave–particle speed. Particles of course never reach the phase velocity of the wave, but are instead driven to an ever-growing velocity, towards the speed of light, while in the wave localization region. We developed a modified average Hamiltonian formalism capable of describing the intricacies of the corresponding dynamics. The modified formalism agrees with simulations and is of particular usefulness in the study of optimum values for the localization length and maximum wave amplitude.

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Phase-space diffusion of charged particles induced by random fluctuations of relative gyrophases in the presence of finite amplitude circularly polarized electromagnetic waves

Physics of Plasmas ◽

10.1063/1.5125600 ◽

2019 ◽

Vol 26 (11) ◽

pp. 112903

Author(s):

Y. Nariyuki

Keyword(s):

Phase Space ◽

Electromagnetic Waves ◽

Charged Particles ◽

Finite Amplitude ◽

Circularly Polarized ◽

Random Fluctuations

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The Jovian ring

International Astronomical Union Colloquium ◽

10.1017/s0252921100101174 ◽

1984 ◽

Vol 75 ◽

pp. 203-209

Author(s):

Joseph A. Burns

Keyword(s):

Equatorial Plane ◽

Charged Particles ◽

Dynamical Evolution ◽

Main Band ◽

Small Grains ◽

Three Components

ABSTRACTLying in Jupiter's equatorial plane is a diaphanous ring having little substructure within its three components (main band, faint disk, and halo). Micron-sized grains account for much of the visible ring, but particles of centimeter sizes and larger must also be present to absorb charged particles. Since dynamical evolution times and survival life times are quite short (≲102-3yr) for small grains, the Jovian ring is being continually replenished; probably most of the visible ring is generated by micrometeoroids colliding into unseen parent bodies that reside in the main band.

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Atomic orientation effects in proton stopping at low velocity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077116 ◽

1983 ◽

Vol 41 ◽

pp. 708-709

Author(s):

Kin Lam

Keyword(s):

Polycrystalline Material ◽

Charged Particles ◽

Target Material ◽

Stopping Power ◽

Low Velocity ◽

Electronic Density ◽

Interatomic Distances ◽

Frame Work ◽

Image Position ◽

Atomic Orientation

The energy of moving ions in solid is dependent on the electronic density as well as the atomic structural properties of the target material. These factors contribute to the observable effects in polycrystalline material using the scanning ion microscope. Here we outline a method to investigate the dependence of low velocity proton stopping on interatomic distances and orientations.The interaction of charged particles with atoms in the frame work of the Fermi gas model was proposed by Lindhard. For a system of atoms, the electronic Lindhard stopping power can be generalized to the formwhere the stopping power function is defined as

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Inelastic scattering at surfaces and interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143560 ◽

1986 ◽

Vol 44 ◽

pp. 392-393

Author(s):

R. H. Ritchie ◽

A. Howie

Keyword(s):

Inelastic Scattering ◽

Surface Properties ◽

Correlation Energy ◽

Condensed Matter ◽

Charged Particles ◽

Condensed Matter Physics ◽

Optical Phonons ◽

Exchange Correlation ◽

Surfaces And Interfaces ◽

Inelastic Interactions

An important part of condensed matter physics in recent years has involved detailed study of inelastic interactions between swift electrons and condensed matter surfaces. Here we will review some aspects of such interactions.Surface excitations have long been recognized as dominant in determining the exchange-correlation energy of charged particles outside the surface. Properties of surface and bulk polaritons, plasmons and optical phonons in plane-bounded and spherical systems will be discussed from the viewpoint of semiclassical and quantal dielectric theory. Plasmons at interfaces between dissimilar dielectrics and in superlattice configurations will also be considered.

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