Kinetic Theory and Simulation of Ultra-Low-Frequency Waves in Magnetospheric Plasmas

磁层等离子体中超低频波的动力学理论与模拟

• 批准号: 0335279
• 负责人: Liu Chen
• 金额: $ 24.6万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-02-15 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0335279&HistoricalAwards=false
• 关键词: Kinetic; Theory; Simulation; Ultra; Low

Satellites regularly observe Ultra-Low Frequency (ULF) waves in the magnetosphere. The observations strongly suggest that the observed waves correspond to nonlinear states of the magnetospheric plasma. This project will concentrate on the theoretical analysis of these waves. An existing linear gyrokinetic-magnetohydrodynamic code will be extended to the nonlinear states. The nonlinear code will then be used to study the excitation and evolution of Alfven waves in a realistic dipole magnetic field. The code will include finite magnetic compression in order to investigate magnetic compressional modes in high-beta plasmas. The linear code will also be further developed to allow it to be used to study kinetic electrostatic instabilities. The code will be used to study the stability properties of ion-temperature-gradient and trapped particle modes in dipole plasmas. Finally, extensive test-particle simulations will be used to study the process of stochastic heating of the particles via wave-particle interactions. The project involves a postdoctoral researcher, a graduate student and an Honor Senior physics major. The results will have direct bearing on satellite observations.

卫星定期观测磁层中的超低频（ULF）波。观测结果有力地表明，观测到的波对应于磁层等离子体的非线性状态。这个项目将集中于这些波浪的理论分析。现有的线性陀螺-磁流体力学代码将扩展到非线性状态。然后将非线性代码用于研究实际偶极磁场中阿尔芬波的激发和演化。代码将包括有限磁压缩，以研究高β等离子体中的磁压缩模式。线性代码也将进一步发展，使其能够用于研究动力学静电不稳定性。该代码将用于研究偶极等离子体中离子温度梯度和捕获粒子模式的稳定性。最后，广泛的测试粒子模拟将用于研究粒子通过波粒相互作用的随机加热过程。该项目涉及一名博士后研究员、一名研究生和一名荣誉大四物理专业学生。这些结果将直接影响卫星观测。