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arXiv · 1709.03673

Electron Surfing and Drift Accelerations in a Weibel-dominated High-Mach-number Shock

Yosuke Matsumoto·Takanobu Amano·Tsunehiko N. Kato·Masahiro Hoshino
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Abstract

How electrons get accelerated to relativistic energies in a high-Mach-number quasi-perpendicular shock is presented by means of ab initio particle-in-cell simulations in three dimensions. We found that coherent electrostatic Buneman waves and ion-Weibel magnetic turbulence coexist in a strong-shock structure whereby particles gain energy during shock-surfing and subsequent stochastic drift accelerations. Energetic electrons that initially experienced the surfing acceleration undergo pitch-angle diffusion by interacting with magnetic turbulence and continuous acceleration during confinement in the shock transition region. The ion-Weibel turbulence is the key to the efficient nonthermal electron acceleration.

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Yosuke Matsumoto, Takanobu Amano, Tsunehiko N. Kato, Masahiro Hoshino. 2017-09-12. Electron Surfing and Drift Accelerations in a Weibel-dominated High-Mach-number Shock. https://doi.org/10.1103/physrevlett.119.105101

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