Dispersive Alfven Waves in Space and Laboratory Plasmas

空间和实验室等离子体中的色散阿尔文波

• 批准号: 0095187
• 负责人: Anatoly Streltsov
• 金额: $ 15万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0095187&HistoricalAwards=false
• 关键词: Dispersive; Alfven; Waves; Space; Laboratory

The investigators will study structural and dynamical features of small-scale, dispersive Alfven waves in magnetized, strongly inhomogeneous, low-beta laboratory and space plasmas. Dispersive Alfven waves generated at the equatorial plane of the magnetosphere may transport electromagnetic power into the ionosphere and can be responsible for small-scale, intense electric fields and currents in the topside auroral ionosphere and in discrete auroral arcs. The study will used a model based on the reduced two-fluid magnetohydrodynamic (MHD) kinetic equations which incorporate effects of finite electron and ion masses, temperatures, and kinetic effects of the finite ion Larmor radious in the fluid description of ultra-low-frequency electromagnetic waves in a magnetized plasma. To understand the range of applicability of the reduced MHD description of dispersive Alfven waves, the investigators will verify the physical model and its numerical implementation on a large set of well-controlled, comprehensive experimental data. In particular, the effort involves testing the results of theoretical models with laboratory plasma experiments performed on the Large Plasma Device at UCLA. Results of the study will be applied to further the capability to interpret intense fields, currents and particle fluxes measured in the auroral zone on rockets and satellites as well as to advance understanding of laboratory plasma experiments.

研究人员将研究磁化、强不均匀、低β实验室和空间等离子体中小规模、色散阿尔文波的结构和动力学特征。 在磁层赤道面产生的色散阿尔文波可以将电磁功率传输到电离层中，并可以在极光电离层和离散极光弧中产生小规模的强电场和电流。 该研究将使用基于简化的二流体磁流体动力学（MHD）动力学方程的模型，该方程在磁化等离子体中超低频电磁波的流体描述中结合了有限电子和离子质量、温度的影响以及有限离子拉莫尔辐射的动力学效应。 为了了解色散阿尔文波的简化 MHD 描述的适用范围，研究人员将在大量受控良好的综合实验数据上验证物理模型及其数值实现。 特别是，这项工作涉及通过在加州大学洛杉矶分校的大型等离子体设备上进行的实验室等离子体实验来测试理论模型的结果。 研究结果将用于进一步解释火箭和卫星极光区测量的强场、电流和粒子通量的能力，并增进对实验室等离子体实验的理解。