Particleincell simulation study of a lowerhybrid shock
Abstract
The expansion of a magnetized highpressure plasma into a lowpressure ambient medium is examined with particleincell simulations. The magnetic field points perpendicular to the plasma's expansion direction and binary collisions between particles are absent. The expanding plasma steepens into a quasielectrostatic shock that is sustained by the lowerhybrid (LH) wave. The ambipolar electric field points in the expansion direction and it induces together with the background magnetic field a fast E cross B drift of electrons. The drifting electrons modify the background magnetic field, resulting in its pileup by the LH shock. The magnetic pressure gradient force accelerates the ambient ions ahead of the LH shock, reducing the relative velocity between the ambient plasma and the LH shock to about the phase speed of the shocked LH wave, transforming the LH shock into a nonlinear LH wave. The oscillations of the electrostatic potential have a larger amplitude and wavelength in the magnetized plasma than in an unmagnetized one with otherwise identical conditions. The energy loss to the drifting electrons leads to a noticeable slowdown of the LH shock compared to that in an unmagnetized plasma.
 Authors:
 Department of Science and Technology, Linköping University, SE60174 Norrköping (Sweden)
 School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22598973
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; COLLISIONS; COMPARATIVE EVALUATIONS; ELECTRIC FIELDS; ELECTRON DRIFT; ELECTRONS; ENERGY LOSSES; IONS; LOWER HYBRID CURRENT DRIVE; LOWER HYBRID HEATING; MAGNETIC FIELDS; NONLINEAR PROBLEMS; OSCILLATIONS; PARTICLES; PLASMA PRESSURE; POTENTIALS; PRESSURE GRADIENTS; SIMULATION; VELOCITY; WAVELENGTHS
Citation Formats
Dieckmann, M. E., Ynnerman, A., Sarri, G., Doria, D., and Borghesi, M.. Particleincell simulation study of a lowerhybrid shock. United States: N. p., 2016.
Web. doi:10.1063/1.4953568.
Dieckmann, M. E., Ynnerman, A., Sarri, G., Doria, D., & Borghesi, M.. Particleincell simulation study of a lowerhybrid shock. United States. doi:10.1063/1.4953568.
Dieckmann, M. E., Ynnerman, A., Sarri, G., Doria, D., and Borghesi, M.. 2016.
"Particleincell simulation study of a lowerhybrid shock". United States.
doi:10.1063/1.4953568.
@article{osti_22598973,
title = {Particleincell simulation study of a lowerhybrid shock},
author = {Dieckmann, M. E. and Ynnerman, A. and Sarri, G. and Doria, D. and Borghesi, M.},
abstractNote = {The expansion of a magnetized highpressure plasma into a lowpressure ambient medium is examined with particleincell simulations. The magnetic field points perpendicular to the plasma's expansion direction and binary collisions between particles are absent. The expanding plasma steepens into a quasielectrostatic shock that is sustained by the lowerhybrid (LH) wave. The ambipolar electric field points in the expansion direction and it induces together with the background magnetic field a fast E cross B drift of electrons. The drifting electrons modify the background magnetic field, resulting in its pileup by the LH shock. The magnetic pressure gradient force accelerates the ambient ions ahead of the LH shock, reducing the relative velocity between the ambient plasma and the LH shock to about the phase speed of the shocked LH wave, transforming the LH shock into a nonlinear LH wave. The oscillations of the electrostatic potential have a larger amplitude and wavelength in the magnetized plasma than in an unmagnetized one with otherwise identical conditions. The energy loss to the drifting electrons leads to a noticeable slowdown of the LH shock compared to that in an unmagnetized plasma.},
doi = {10.1063/1.4953568},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}

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