3D electromagnetic PIC simulations of relativistic electron pulse injections from spacecraft
TL;DR: In this article, the initial stage of the beam injection process is simulated by a fully electromagnetic and relativistic Particle-in-Cell (PIC) code, and the selfconsistent implementation of electric charging of a spacecraft structure in an electromagnetic code is demonstrated, and beam propagation dynamics is explored for a range of beam to ambient plasma densities.
About: This article is published in Advances in Space Research.The article was published on 2002-01-01. It has received 5 citations till now. The article focuses on the topics: Relativistic electron beam & Relativistic particle.
Citations
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TL;DR: In this article, the relativistic electron beam injection process is investigated by means of 3-dimensional particle-in-cell (PIC) simulations to determine the initial interaction of the beam with the spacecraft and the ambient plasma.
16 citations
TL;DR: In this paper, two postmission disposal (PMD) parametric analyses based on the high fidelity NASA orbital debris evolutionary model LEGEND were conducted to evaluate the impact of a prolonged spacecraft mission lifetime and a lower PMD success rate on the long-term debris environment.
15 citations
TL;DR: In this article, the relativistic electron beam injection process is investigated by means of three-dimensional particle-in-cell simulations to determine the initial interaction of the beam with the spacecraft and the ambient plasma.
Abstract: [1] Linear accelerators producing relativistic (5 MeV) electron beams are now down to a size that allows them to be flown on spacecraft and sounding rockets. This opens up new opportunities for atmospheric/ionospheric modification experiments where the mesosphere and lower thermosphere regions can be perturbed down to 40-km altitude. In this paper the relativistic electron beam injection process is investigated by means of three-dimensional particle-in-cell simulations to determine the initial interaction of the beam with the spacecraft and the ambient plasma. The results indicate that relativistic beams are more stable than keV-energy beams investigated in the past, allowing the injection and propagation of beams with currents several orders of magnitude higher than those for keV-energy beams. The superior stability of relativistic beams is the result of a combination of effects including the higher relativistic electron mass, a lower beam density, and a smaller effect from spacecraft charging. Relativistic beams injected downward from spacecraft are therefore expected to deposit a large fraction of the energy in the middle atmosphere. In the high-current limit (I > 100 A) the beam self-fields are strong. In this regime a beam may propagate in the ion-focused regime, where beam electrons expel ambient electrons to create a channel of ambient ions that space charge neutralize the beam. The establishment of the ion channel, however, creates significant turbulence and scattering.
10 citations
12 Dec 2001
TL;DR: In this paper, the authors developed computational tools and used them to better assess relavistic beam launch, propagation, and interaction with the space environment and atmosphere using particle-in-cell (PIC) techniques.
Abstract: : Models for propagation physics and associated ionospheric/atmospheric modification have been developed for the space-based injection of relativistic (E(-) 1-100 MeV) electron beams. Initial evaluations of beam propagation effects in the ionosphere, magnetosphere, and atmosphere have been conducted. The overall goal of this work was to develop computational tools and use them to better assess relavistic beam launch, propagation, and interaction with the space environment and atmosphere. Computational tools developed and then applied to this problem. include models addressing: beam propagation using an envelope equation; integrated beam-atmosphere interactions (This model contains time-dependent chemistry effects necessary to compute optical emissions as a function of altitude); beam launch and propagation using particle-in-cell (PIC) techniques; and magnetospheric propagation and plasma transport (Khazanov models). It is concluded that for practical beam energies and current the beam propagation is stable This is done theoretically and using the PIC modeling. Over long distance propagation the Khazanov models were able to show that the beam particles will scatter in pitch-angle and relative location, but lifetimes are expected to be similar to those found for the radiation belts for nearly equatorial mirroring injection.
7 citations
TL;DR: In this article, a series of 2D particle-in-cell simulations were performed and an analytical model of ion channel oscillation was constructed according to the single-particle motion, which showed that when the beam density is higher than the density of plasma environment, ion channel always continues to oscillate periodically over the entire propagation.
Abstract: It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its long-range propagation in the space plasma environment. Most prior studies discussed the focusing characteristics of the beam in the ion channel, but the establishment process and transient properties of the ion channel itself, which also plays a crucial role during the propagation of the relativistic electron beam in the plasma environment, were commonly neglected. In this study, a series of two-dimensional (2D) particle-in-cell simulations is performed and an analytical model of ion channel oscillation is constructed according to the single-particle motion. The results showed that when the beam density is higher than the density of plasma environment, ion channel can be established and always continues to oscillate periodically over the entire propagation. Multiple factors, including the beam electron density, initial beam radius, and the plasma density can affect the oscillation properties of ion channel. Axial velocity of the beam oscillates synchronously with the ion channel and this phenomenon will finally develop into a two-stream instability which can seriously affect the effective transport for relativistic electron beam. Choosing appropriate beam parameters based on various plasma environments may contribute to the improvement of the stability of ion channel. Additionally, radial expansion of the beam can be limited by ion channel and a stable long-range propagation in terrestrial atmosphere may be achieved.
References
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Book•
01 Sep 1988
TL;DR: In this article, Beam optics and focusing systems Laminar and non-Laminar beams with self-fields without collisions, beacons with scattering or dissipation waves and instabilities in beams
Abstract: Introduction Beam optics and focusing systems Laminar beams with self-fields Non-Laminar beams without collisions Beams with scattering or dissipation Waves and instabilities in beams
613 citations
Book•
01 Apr 1990
TL;DR: In this paper, the phase space description of Charged Particle Beams is presented. But the authors do not specify the phase of the phase in terms of the Beam Emittance.
Abstract: Phase Space Description of Charged Particle Beams Introduction to Beam Emittance Beam Emittance - Advanced Topics Introduction to Beam-Generated Forces Beam-Generated Forces - Advanced Topics Electron and Ion Guns High Power Pulsed Electron and Ion Diodes Paraxial Beam Transport with Space-Charge High Current Electron Beam Transport in Vacuum Ion Beam Neutralization Electron Beams in Plasmas Transverse Instabilities Longitudinal Instabilities Energy Extraction from Beams.
445 citations
Book•
01 Jan 1993
233 citations
TL;DR: In this article, the authors examined selected results from experiments, performed in 1980s, involving the ejection of beams of electrons from spacecraft, and special attention was given to the basic processes associated with the spacecraft charging, passive current collection, beam-atmosphere interactions, beamplasma interactions, and neutral gas emission.
77 citations
TL;DR: In this article, it is shown that the earth's magnetic field severely limits the radial expansion of the beam otherwise induced by electron-neutral collisions, and the so-called envelope-equations from high-energy laboratory physics adequately describe beam propagation in the upper atmosphere.
Abstract: Linear accelerators (linacs), capable of producing 5 MeV energy electron beams at 80 mA currents, are now down to a size that allow them to be flown on sounding rockets or balloons. This opens up new opportunities for atmospheric/ionospheric modification experiments where the mesosphere and thermosphere regions of the atmosphere can be perturbed down to 40 km altitude. In this paper beam propagation and atmospheric perturbation effects are studied by Monte Carlo simulations and by analytical means. It is shown that the earth' magnetic field severely limits the radial expansion of the beam otherwise induced by electron-neutral collisions. It is also shown that the so-called “envelope-equations” from high-energy laboratory physics adequately describe beam propagation in the upper atmosphere. The plasma density and electric conductivity modifications to the atmosphere are calculated from the Monte Carlo simulations. Inside the beam the conductivity in the 40–50 km altitude region is enhanced more than one order of magnitude by a 10 µs-duration pulse. Some ideas for future scientific investigations are discussed, including the generation of electrical discharges by beams injected over thunderstorm regions.
24 citations