Effects of trapped electrons on ion reflection in an oblique shock wave
Abstract
A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The trapped electrons excite twodimensional (2D) electromagnetic fluctuations with finite wavenumbers along the shock front. We study effects of the trapped electrons on ion motions through the 2D fluctuations. It is analytically shown that the fraction of ions reflected from the shock front is enhanced by the 2D fluctuations. This is confirmed by 2D (two space coordinates and three velocities) relativistic, electromagnetic particle simulations with full ion and electron dynamics and calculation of test ions in the electromagnetic fields averaged along the shock front. A comparison between 2D and onedimensional electromagnetic particle simulations is also shown.
 Authors:
 National Institute for Fusion Science, Toki 5095292 (Japan)
 Department of Physics Nagoya University, Nagoya 4648602 (Japan)
 Publication Date:
 OSTI Identifier:
 22490930
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPARATIVE EVALUATIONS; ELECTROMAGNETIC FIELDS; FLUCTUATIONS; IONS; MAGNETIC FIELDS; ONEDIMENSIONAL CALCULATIONS; RELATIVISTIC RANGE; SHOCK WAVES; TRAPPED ELECTRONS; TWODIMENSIONAL CALCULATIONS; TWODIMENSIONAL SYSTEMS; VELOCITY
Citation Formats
Toida, Mieko, Email: toida.mieko@nifs.ac.jp, and Inagaki, Junya. Effects of trapped electrons on ion reflection in an oblique shock wave. United States: N. p., 2015.
Web. doi:10.1063/1.4922847.
Toida, Mieko, Email: toida.mieko@nifs.ac.jp, & Inagaki, Junya. Effects of trapped electrons on ion reflection in an oblique shock wave. United States. doi:10.1063/1.4922847.
Toida, Mieko, Email: toida.mieko@nifs.ac.jp, and Inagaki, Junya. Mon .
"Effects of trapped electrons on ion reflection in an oblique shock wave". United States.
doi:10.1063/1.4922847.
@article{osti_22490930,
title = {Effects of trapped electrons on ion reflection in an oblique shock wave},
author = {Toida, Mieko, Email: toida.mieko@nifs.ac.jp and Inagaki, Junya},
abstractNote = {A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The trapped electrons excite twodimensional (2D) electromagnetic fluctuations with finite wavenumbers along the shock front. We study effects of the trapped electrons on ion motions through the 2D fluctuations. It is analytically shown that the fraction of ions reflected from the shock front is enhanced by the 2D fluctuations. This is confirmed by 2D (two space coordinates and three velocities) relativistic, electromagnetic particle simulations with full ion and electron dynamics and calculation of test ions in the electromagnetic fields averaged along the shock front. A comparison between 2D and onedimensional electromagnetic particle simulations is also shown.},
doi = {10.1063/1.4922847},
journal = {Physics of Plasmas},
number = 6,
volume = 22,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}

A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The effect of trapped electrons on electromagnetic fields in a shock wave is studied by theory and particle simulations. The expressions for field strengths are analytically obtained, including the number of trapped electrons n{sub t} as a factor. It is shown that as n{sub t} increases, the magnitude of F increases, where F is the integral of the parallel electric field, E{sub }=(E{center_dot}B)/B, along B. Theoretical analysis also suggests that the increase in F causes the electrons to be trappedmore »

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A magnetosonic shock wave propagating obliquely to a magnetic field is studied by theory and simulation, with particular attention to the resonant ion acceleration (the v/sub p/ x B acceleration) by the shock. Theoretical analysis based on a twofluid model shows that, in the laminar shock, the electric field strength in the direction normal to the wave is about (m/sub i//m/sub e/) /sup //S times larger for the quasiperpendicular shock than that for the quasiparallel shock, which is a reflection of the fact that the width of the quasiperpendicular shock is much smaller than that of the quasiparallel shock. Timemore »