CAREER: Effects of the Magnetosheath Properties on the Dynamics and Plasma Transport Produced by the Kelvin-Helmholtz Instability and on the Plasma Sheet Anisotropies

该奖项由2009年美国复苏和再投资法案(公法111-5)资助。该项目的主要科学目标是在全球范围内了解地球磁层-电离层系统上的开尔文-亥姆霍兹不稳定性(KHI)。特别是，将研究太阳风参数和由此产生的磁鞘特性对KHI的影响。由I)KHI和II)KAW(KAW)产生的效应。磁鞘性质对等离子体片内观察到的离子温度各向异性的影响也将被确定。这项调查将使用星系团和Themis航天器几年来从低纬磁层顶交叉点和磁鞘获得的数据。数据分析方法包括各种方差分析技术、到deHoffman Teller参照系的变换、Walen关系、多航天器方法以及各种频谱分析方法。数据分析结果将与二维和三维高分辨率磁流体力学(MHD)模拟进行比较。KHI引起的粒子动力学将通过使用3-D本地MHD程序中的测试粒子并与观测到的离子分布函数进行比较来研究。磁鞘过程将通过对磁鞘性质的统计研究和利用全局混合(流体电子、重离子)模拟来研究。此外，磁流体尺度的KHI将与混合和完全动力学模拟的不稳定性进行比较。火星和金星上的KHI也将用这些模拟进行研究，来自火星和金星轨道器的数据将用于与模拟结果进行比较。这项研究将涉及几个专题：1)在地球磁层发生KHI的统计研究以及相关的磁鞘和等离子体片性质；2)马赫数和等离子体β对由KHI产生的等离子体输运的影响；3)KHI和磁鞘过程和性质对等离子体片黎明-黄昏不对称性的影响；4)磁层KHI与电离层的耦合；5)对KHD、混合和动力学模拟KHI的比较；6)研究火星和金星的开尔文-亥姆霍兹不稳定性。这些专题对于理解全球磁层动力学、空间等离子体的跨尺度耦合以及非磁化行星附近的等离子体动力学具有重要意义。这项研究的结果将是对地球空间环境建模(GEM)计划目标的重要贡献。这项研究符合当前GEM的几个焦点小组：等离子体进入磁尾和磁尾内的输运；前震、弓形激波和磁鞘；MIC全球耦合。统计学研究将成为恩布里-里德尔航空大学(ERAU)2009年秋季开始的工程物理新博士项目研究生博士论文工作的核心。由此产生的研究论文将发表在专门研究空间科学和等离子体科学的被引用的科学期刊上。该项目将开发一个网站，并在那里突出学生的研究。该项目将包括一个公共外联方案，从2009年秋季开始在代托纳海滩艺术和科学博物馆组织一系列空间科学研讨会。这项研究通过将本科生纳入暑期研究项目，将研究和教育结合在一起。此外，国际和平研究所将开设一门研究生课程：“航天器数据分析方法”，学生可以通过利用航天器数据学习单航天器和多航天器数据分析技术。ERAU促进代表不足群体的平等机会。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The primary science objective of this project is to gain a global understanding of the Kelvin-Helmholtz Instability (KHI) on Earth's magnetosphere-ionosphere system. In particular the effects of the solar wind parameters and resulting magnetosheath properties on the KHI will be studied. The effects generated by i) KHI and ii) Kinetic-Alfvén waves (KAW). The effects of the magnetosheath properties on ion temperature anisotropies observed within the plasma sheet will also be determined. The investigation will use several years of Cluster and Themis spacecraft data from low-latitude magnetopause crossings and magnetosheath. Data analysis methods include various variance analysis techniques, transformation to the deHoffman Teller reference frame, Walen relation, multi-spacecraft methods, and a variety of spectral analysis methods. The data analysis results will be compared with 2-D and 3-D high-resolution magnetohydrodynamic (MHD) simulations. The particle dynamics due to KHI will be studied by using test-particles within a 3-D, local MHD code and comparisons with observed ion distribution functions. The magnetosheath processes will be studied by doing a statistical study of the magnetosheath properties and by utilizing global hybrid (fluid electrons, paritlce ions) simulations. In addition, the MHD-scale KHI will be compared with hybrid and fully kinetic simulations of the instability. The KHI at Mars and Venus will also be studied with these simulations and data from Mars and Venus orbiters will be utilized for comparisons with the simulation results. The study will address several topics: 1) The statistical study of the occurrence of the KHI at the Earth's magnetosphere and the associated magnetosheath and plasma sheet properties; 2) The influence of the Mach numbers and plasma beta on the plasma transport produced by the KHI; 3) The effects of the KHI and magnetosheath processes and properties on the dawn-dusk asymmetries of the plasma sheet; 4) The coupling of the magnetospheric KHI into the ionosphere; 5) Comparison between MHD, hybrid and kinetic simulations of the KHI; 6) The study of the Kelvin-Helmholtz Instability at Mars and Venus. These topics are of central importance for understanding the global magnetospheric dynamics, cross-scale coupling of space plasmas, and plasma dynamics in the vicinity of non-magnetized planets. Results of the study will be an important contribution to the goals of the Geospace Environment Modeling (GEM) program. This research fits under several current GEM Focus Groups: Plasma Entry and Transport into and within the Magnetotail; Foreshock, Bow Shock and Magnetosheath; MIC Global Coupling. The statistical studies will form the core of the Ph.D thesis work of a graduate student in a new Ph.D program in Engineering Physics starting in Fall-2009 at Embry-Riddle Aeronautical University (ERAU). The resulting research papers will be published in refereed scientific journals devoted to space science and plasma science. The project will develop a web site and the student research will be highlighted there. The project will include a public outreach program by organizing a space sciences seminar series at Daytona Beach Museum of Arts and Sciences starting in the Fall of 2009. The study integrates research and education by including undergraduate students in a summer research program. In addition, the PI will develop a graduate course: "Spacecraft Data-Analysis Methods", where students can learn single- and multi-spacecraft data-analysis techniques by utilizing spacecraft data. The ERAU promotes equal opportunities for the underrepresented groups.