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

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目的主要科学目标是获得对地球磁层-电离层系统的开尔文-亥姆霍兹不稳定性（KHI）的全球了解。特别是太阳风参数和由此产生的磁鞘特性对KHI的影响将进行研究。由i）KHI和ii）动力阿尔文波（KAW）产生的效应。磁鞘的离子温度各向异性的等离子体片内观察到的属性的影响也将被确定。这项调查将使用多年来从低纬度磁层顶交叉和磁鞘收集的星团和忒弥斯航天器数据。数据分析方法包括各种方差分析技术、转换到deHoffman Teller参考系、Walen关系、多航天器方法和各种光谱分析方法。数据分析结果将与2-D和3-D高分辨率磁流体动力学（MHD）模拟进行比较。由于KHI的粒子动力学将通过使用测试粒子在3-D，本地MHD代码和观察到的离子分布函数的比较进行研究。磁鞘过程将通过磁鞘特性的统计研究和利用全球混合（流体电子，paritlce离子）模拟来研究。此外，MHD规模的KHI将与混合动力和完全动力学模拟的不稳定性进行比较。还将利用这些模拟研究火星和金星的KHI，并将利用来自火星和金星轨道器的数据与模拟结果进行比较。该研究将涉及几个主题：1）统计研究地球磁层中KHI的发生以及相关的磁鞘和等离子体片特性; 2）马赫数和等离子体β对KHI产生的等离子体输运的影响; 3）KHI和磁鞘过程和特性对等离子体片的晨昏不对称性的影响; 4）磁层KHI与电离层的耦合; 5）KHI的MHD、混合和动力学模拟的比较; 6）火星和金星Kelvin-Helmholtz不稳定性的研究。这些主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核心重要性。研究结果将对地球空间环境建模（GEM）计划的目标做出重要贡献。这项研究符合目前的几个GEM焦点小组：等离子体进入和运输到磁尾内;前震，弓冲击和磁鞘; MIC全球耦合。统计研究将形成一个新的工程物理博士学位课程的研究生博士论文工作的核心，该课程将于2009年秋季在安柏瑞德航空大学（ERAU）开始。由此产生的研究论文将发表在专门讨论空间科学和等离子体科学的经评审的科学期刊上。该项目将开发一个网站，学生的研究将突出显示。该项目将包括一个公共宣传方案，从2009年秋季开始在代托纳海滩艺术和科学博物馆举办一系列空间科学研讨会。这项研究通过将本科生纳入夏季研究计划，将研究和教育结合起来。此外，研究所还将开设一门研究生课程：“航天器数据分析方法”，学生可在该课程中学习利用航天器数据进行单航天器和多航天器数据分析的技术。ERAU促进代表性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.