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arXiv · 1909.03337

Precursor Wave Amplification by Ion-Electron Coupling through Wakefield in Relativistic Shocks

Masanori Iwamoto·Takanobu Amano·Masahiro Hoshino·Yosuke Matsumoto·Jacek Niemiec·Arianna Ligorini·Oleh Kobzar·Martin Pohl
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Abstract

We investigated electromagnetic precursor wave emission in relativistic shocks by using two-dimensional particle-in-cell simulations. We found that the wave amplitude is significantly enhanced by a positive feedback process associated with ion-electron coupling through the wakefields for high magnetization. The wakefields collapse during the nonlinear process of the parametric decay instability in the near-upstream region, where nonthermal electrons and ions are generated. The intense coherent emission and the particle acceleration may opperate in high-energy astrophysical objects.

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Masanori Iwamoto, Takanobu Amano, Masahiro Hoshino, Yosuke Matsumoto, Jacek Niemiec, Arianna Ligorini, Oleh Kobzar, Martin Pohl. 2019-09-07. Precursor Wave Amplification by Ion-Electron Coupling through Wakefield in Relativistic Shocks. https://doi.org/10.3847/2041-8213/ab4265

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