Ring Current Ion Interaction with Magnetospheric Hydromagnetic Waves

环流离子与磁层水磁波的相互作用

• 批准号: 9212000
• 负责人: Mary Hudson
• 金额: $ 24.16万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1996-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9212000&HistoricalAwards=false
• 关键词: Ring; Current; Ion; Interaction; Magnetospheric

The primary objectives of the proposed project is to advance understanding of the interaction of ring current ions with magnetospheric hydromagnetic waves. In particular, wave excitation by magnetic drift-bounce resonance with energetic (100-200 keV) ring current protons and the self-consistent nonlinear evolution of the waves and the ring current ions (H+ and O+) will be considered. The methods employed will include (i) numerical solutions of linear gyrokinetic eigenmode equations using existing computer codes, (ii) simulations of the motion of ring current ions in hydromagnetic waves using an existing gyroaveraged Hamiltonian test particle code, (iii) development of a 3D dipole geometry magnetohydrodynamic (MHD) code and (iv) coupling of the test-particle and MHD codes to produce a hybid MHD-gyrokinetic code. The hybrid code will be developed separately on a CRAY-YMP computer and also on a massively paralle CM-2 Connection Machine. It is expected that the CM-2 MHD- gyrokinetic simulation system will be faster than the CRAY version and will be capable of handling a larger simulation region. The results will provide the first simulation of the excitation and nonlinear evolution of magnetospheric hydromagnetic waves due to ring current ions, and of the self-consistent effect of the waves on the ions. Comparisons with spacecraft data will be made to test the theoretical predictions and yield new theoretical insights into observed wave properties and associated particle measurements.

拟议项目的主要目标是增进对环流离子与磁层水磁波相互作用的了解。特别地，将考虑高能(100-200keV)环流质子的磁漂跳共振激发波，以及波和环流离子(H+和O+)的自洽非线性演化。所采用的方法将包括(I)使用现有的计算机程序数值求解线性回转动力学本征模式方程，(Ii)使用现有的回转平均哈密顿测试粒子程序模拟环电流离子在流体磁波中的运动，(Iii)开发3D偶极几何磁流体(MHD)程序，以及(Iv)将测试粒子和MHD程序耦合以产生混合MHD-回转动力学程序。混合代码将分别在Cray-YMP计算机和大规模并行CM-2连接机上开发。预计CM-2磁流体陀螺动力学仿真系统将比Cray版本更快，并将能够处理更大的仿真区域。这些结果将首次模拟环电流离子对磁层水磁波的激发和非线性演化，以及磁层水磁波对离子的自洽效应。将与航天器数据进行比较，以检验理论预测，并对观测到的波特性和相关粒子测量产生新的理论见解。