TY - JOUR A1 - Iwamoto, Masanori A1 - Amano, Takanobu A1 - Hoshino, Masahiro A1 - Matsumoto, Yosuke A1 - Niemiec, Jacek A1 - Ligorini, Arianna A1 - Kobzar, Oleh A1 - Pohl, Martin T1 - Precursor Wave Amplification by Ion-Electron Coupling through Wakefield in Relativistic Shocks JF - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters N2 - 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 operate in high-energy astrophysical objects. Y1 - 2019 U6 - https://doi.org/10.3847/2041-8213/ab4265 SN - 2041-8205 SN - 2041-8213 VL - 883 IS - 2 PB - IOP Publ. Ltd. CY - Bristol ER -