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

卫星定期观测磁层中的超低频波。 观测结果强烈地表明，观测到的波对应于磁层等离子体的非线性状态。 这个项目将集中在这些波的理论分析。 现有的线性回旋-磁流体动力学代码将扩展到非线性状态。 然后，非线性代码将被用来研究阿尔芬波在一个现实的偶极磁场的激发和演变。 该代码将包括有限的磁压缩，以调查高β等离子体中的磁压缩模式。 线性代码也将进一步发展，使其被用来研究动力学静电不稳定性。 该程序将用于研究偶极等离子体中离子温度梯度模和俘获粒子模的稳定性。 最后，广泛的测试粒子模拟将被用来研究通过波粒相互作用的粒子的随机加热过程。 该项目涉及一名博士后研究员、一名研究生和一名物理专业荣誉大四学生。 结果将对卫星观测产生直接影响。

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.