[P-EM15] 宇宙プラズマ理論・シミュレーション

[PEM15-04] 電子・イオンプラズマ中のシンクロトロンメーザー不安定性

*松清 修一¹、江崎 陽大²、岩本 昌倫¹ (1.九州大学大学院総合理工学研究院、2.九州大学総合理工学府)

キーワード：シンクロトロンメーザー不安定性、粒子加速、PICシミュレーション

Synchrotron maser instability driven by relativistic ring distribution of electrons and ions is investigated. The linear analysis reveals that the electron and ion instabilities have characteristic frequencies and wavenumbers proportional to the mass of electrons and ions, respectively, as pointed out in a previous study. The generated waves have both electromagnetic and electrostatic features. The latter feature becomes remarkable when wave phase velocity is below the speed of light. PIC simulation further reveals that the electron instability seldom affects the ion instability due to the large difference of inertial. The ion instability destabilizes larger amplitude waves. In the simulation strong transverse electric field with zero wavenumber is generated. This electric field efficiently accelerates some electrons which are pre-accelerated in the early stage of the simulation due to the electron instability. These electrons finally have the energy comparable to the maximum ion energy. Furthermore, the accelerated electrons excite secondary electron instability. Some parameter dependenses will also be discussed.