STUDY OF ELECTROMAGNETIC RADIATION FROM ELECTROSTATIC' SOLITARY WAVES IN SPACE PLASMAS

空间等离子体中静电孤波的电磁辐射研究

• 批准号: 13440143
• 负责人: OMURA Yoshiharu
• 金额: $ 8.96万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440143/
• 关键词: electrostatic solitary wave; GEOTAIL; plasma waves; computer simulation; induced electric field; MPI; electrostatic potential; space plasmas; HPI; GEOTAL; HPF

We have developed a new method to realize an efficient absorbing boundary for ele'ctro hagnetic particle simulations with a minimal size of the damping region. We have also developed a new algorithm of the charge conservation method for current density calculation, which substantially reduced the computation. We have demonstrated existence of higher harmonics of Langmuir waves enhanced by an electron beam by a newly developed Vlasov code. In an open system with the absorbing boundaries, we traced a long time and long distance evolution of the electron beam instability, showing formation of electrostatic solitary waves and their coupling with oblique whistler waves and lower, hybrid waves, which are localized in the region close to the electron beam generation region. In the two dimensional system, we find the electrostatic solitary waves are accompanied by electromagnetic components due to the localized current driven by the ExB drift associated with the perpendicular electric field of two-dimensional electrostatic potentials. We found an electron beam formation through Buneman instability driven by an induced electric field in the boundary layers of the magnetosphere. The structure and characteristics of electrostatic waves were analyzed theoretically, and the analysis was also extended to a three dimensional model. We obtained the necessary conditions for existence of isolated three-dimensional potentials.

我们开发了一种新方法，可以以最小的阻尼区域尺寸实现电磁粒子模拟的有效吸收边界。我们还开发了一种用于电流密度计算的电荷守恒法的新算法，大大减少了计算量。我们已经通过新开发的弗拉索夫代码证明了电子束增强的朗缪尔波高次谐波的存在。在具有吸收边界的开放系统中，我们追踪了电子束不稳定性的长时间和长距离演化，显示了静电孤立波的形成及其与斜哨声波和较低的混合波的耦合，这些波位于靠近电子束生成区域的区域。在二维系统中，我们发现由于与二维静电势的垂直电场相关的ExB漂移驱动的局域电流，静电孤立波伴随着电磁分量。我们发现电子束是通过磁层边界层中的感应电场驱动的布内曼不稳定性形成的。从理论上分析了静电波的结构和特性，并将分析推广到三维模型。我们得到了孤立三维势存在的必要条件。

项目成果

T.Umeda, Y.Omura, H.Matsumoto, H.Usui: "Formation of electrostatic solitary waves in space plasmas : Particle simulations with open boundary conditions"Journal of Geophysical Research. 107・A12. doi:10.1029/2001JA000286 (2002)

T.Umeda、Y.Omura、H.Matsumoto、H.Usui：“空间等离子体中静电孤立波的形成：开放边界条件下的粒子模拟”地球物理研究杂志 107・A12 doi：10.1029/2001JA000286（2002）。

T.Umeda, Y.Omura, P.H.Yoon, R.Gae 1 zer, H.Matsumoto: "Harmonic Langmuir waves. III. Vlasov simulation"Physics of Plasmas. vol. 10, no. 2. P382-P391 (2003)

T.Umeda、Y.Omura、P.H.Yoon、R.Gae 1 zer、H.Matsumoto：“谐波朗缪尔波。III.Vlasov 模拟”等离子体物理学。

Y.Omura, H.Kojima, T.Umeda, H.Matsumoto: "Observational evidence of dissipative small scale processes : GEOTAIL spacecraft observation and simulation of electrostatic solitary waves"Astrophysics and Space Science. 277. 45-57 (2001)

Y.Omura、H.Kojima、T.Umeda、H.Matsumoto：“耗散小尺度过程的观测证据：GEOTAIL 航天器静电孤立波的观测和模拟”天体物理学和空间科学。

Y.Omura, V.L.Krasovsky: "Comments on "Electrostatic wave variety and the origin of BEN""Planetary and Space Science. 50. 343-346 (2002)

Y.Omura、V.L.Krasovsky：“对“静电波变化和 BEN 起源”的评论”《行星与空间科学》。

T.Umeda, Y.Omura, T.Tominaga, H.Matsumoto: "A new charge conservation method in electromagnetic particle-in-cell simulations"Computer Physics Communications. 156・1. 73-85 (2003)

T.Umeda、Y.Omura、T.Tominaga、H.Matsumoto：“细胞内电磁粒子模拟中的新电荷守恒方法”计算机物理通信 156・1（2003 年）。