Nonlinear evolution of Buneman instability and its implication for electron acceleration in high Mach number collisionless perpendicular shocks
Abstract
Nonlinear evolution of the Buneman instability and its application to electron acceleration in collisionless shocks are discussed. Twodimensional particleincell simulations show that the saturation level of the instability is reduced from onedimensional simulation results. It is demonstrated that the reduced saturation level is due to the resonant waveparticle interactions with large amplitude obliquely propagating waves. A new estimate for the saturation level is given by considering the interactions with oblique modes. The effects of the large amplitude oblique modes on electron shock surfing acceleration that is mainly controlled by the Buneman instability are also investigated. Twodimensional particleincell simulations of the shock transition region are performed by adopting a local model with the periodic boundary condition. The results indicate that the presence of oblique modes introduces a stochastic behavior to the trajectories of energetic electrons. The maximum energy is limited by the finite lifetime of the instability in the present periodic model. However, this will not be the case in the realistic shock transition region. The application to realistic shocks with Mach numbers typical of supernova remnants is also discussed.
 Authors:
 Department of Physics, Nagoya University, Nagoya 4648602 (Japan)
 Department of Earth and Planetary Science, University of Tokyo, Tokyo 1130033 (Japan)
 Publication Date:
 OSTI Identifier:
 21272725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 16; Journal Issue: 10; Other Information: DOI: 10.1063/1.3240336; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATION; MACH NUMBER; NONLINEAR PROBLEMS; PARTICLE INTERACTIONS; PLASMA INSTABILITY; PLASMA SIMULATION; SHOCK WAVES; STOCHASTIC PROCESSES; SUPERNOVA REMNANTS; TAIL ELECTRONS; TWODIMENSIONAL CALCULATIONS
Citation Formats
Amano, Takanobu, and Hoshino, Masahiro. Nonlinear evolution of Buneman instability and its implication for electron acceleration in high Mach number collisionless perpendicular shocks. United States: N. p., 2009.
Web. doi:10.1063/1.3240336.
Amano, Takanobu, & Hoshino, Masahiro. Nonlinear evolution of Buneman instability and its implication for electron acceleration in high Mach number collisionless perpendicular shocks. United States. doi:10.1063/1.3240336.
Amano, Takanobu, and Hoshino, Masahiro. Thu .
"Nonlinear evolution of Buneman instability and its implication for electron acceleration in high Mach number collisionless perpendicular shocks". United States.
doi:10.1063/1.3240336.
@article{osti_21272725,
title = {Nonlinear evolution of Buneman instability and its implication for electron acceleration in high Mach number collisionless perpendicular shocks},
author = {Amano, Takanobu and Hoshino, Masahiro},
abstractNote = {Nonlinear evolution of the Buneman instability and its application to electron acceleration in collisionless shocks are discussed. Twodimensional particleincell simulations show that the saturation level of the instability is reduced from onedimensional simulation results. It is demonstrated that the reduced saturation level is due to the resonant waveparticle interactions with large amplitude obliquely propagating waves. A new estimate for the saturation level is given by considering the interactions with oblique modes. The effects of the large amplitude oblique modes on electron shock surfing acceleration that is mainly controlled by the Buneman instability are also investigated. Twodimensional particleincell simulations of the shock transition region are performed by adopting a local model with the periodic boundary condition. The results indicate that the presence of oblique modes introduces a stochastic behavior to the trajectories of energetic electrons. The maximum energy is limited by the finite lifetime of the instability in the present periodic model. However, this will not be the case in the realistic shock transition region. The application to realistic shocks with Mach numbers typical of supernova remnants is also discussed.},
doi = {10.1063/1.3240336},
journal = {Physics of Plasmas},
number = 10,
volume = 16,
place = {United States},
year = {Thu Oct 15 00:00:00 EDT 2009},
month = {Thu Oct 15 00:00:00 EDT 2009}
}

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