SHINE: Instabilities Driven by Anisotropic Ion and Electron Beams in the Solar Wind: Analytical Theory, Numerical Simulations, and In-Situ Observations

SHINE：太阳风中各向异性离子和电子束驱动的不稳定性：分析理论、数值模拟和现场观测

• 批准号: 1460190
• 负责人: Kai Germaschewski
• 金额: $ 35.7万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-15 至 2020-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1460190&HistoricalAwards=false
• 关键词: SHINE; Instabilities; Driven; Anisotropic; Ion

This 3-year SHINE project aims to apply a fundamental approach to tackle plasma instabilities driven by anisotropic ion and electron beams in the solar wind, and to improve our understanding of micro-instabilities in general. The project will combine the analysis of linear and nonlinear effects, and create a multidisciplinary collaboration among experts in theory, numerical simulation, and observation, with relevance to many plasma systems. The research project will support two young researchers in early phases of their careers and one undergraduate student. The project team will engage local schools within the University of New Hampshire's Upward Bound program, which is designed to help high-school students from low-income families and/or first-generation potential college students succeed in higher education. This activity will provide the students with a unique opportunity to explore the field of space science. The research and EPO agenda of this project supports the Strategic Goals of the AGS Division in discovery, learning, diversity, and interdisciplinary research.This SHINE project involves an integrated and multidisciplinary four-step research program to elucidate the interplay between anisotropies and beams in the distribution functions of both ions and electrons in the solar wind by means of analytical theory, numerical studies, and in-situ observations. The project team will formulate a generalized theory for the instability thresholds of anisotropic and beamed ions and electrons in the solar wind by building on previously developed methods. Numerical solutions of the hot-plasma dispersion relation will allow the project team to verify the analytical findings. The project activities will include hybrid simulations to investigate the nonlinear evolution of the ion instabilities. In the case of electron-driven instabilities, a full particle-in-cell code will help the team investigate the nonlinear evolution of the plasma and the excited waves. The theoretical and numerical results from this project will be compared with observations of plasma and wave properties in the solar wind. The project efforts will be focused on answering the following key scientific question: what determines the thresholds and nonlinear evolution of instabilities driven by anisotropic ion and electron beams in the solar wind? The answer to this question is of paramount interest to the heliophysics community, since physics-driven solar-wind models critically depend on a detailed understanding of the relevant microphysical processes that regulate non-thermal features in the ion and electron distribution functions.

这个为期3年的SHINE项目旨在应用一种基本方法来解决太阳风中各向异性离子和电子束驱动的等离子体不稳定性，并提高我们对微观不稳定性的理解。 该项目将联合收割机的线性和非线性效应的分析，并创建一个多学科的理论，数值模拟和观察专家之间的合作，与许多等离子体系统。 该研究项目将支持两名处于职业生涯早期阶段的年轻研究人员和一名本科生。 该项目团队将在新罕布什尔州大学的“向上发展”项目中与当地学校合作，该项目旨在帮助来自低收入家庭的高中生和/或第一代潜在的大学生在高等教育中取得成功。 这项活动将为学生提供一个独特的机会，探索空间科学领域。 该项目的研究和EPO议程支持AGS部门在发现，学习，多样性和跨学科研究方面的战略目标。该SHINE项目包括一个综合的多学科四步研究计划，通过分析理论，数值研究和现场观测来阐明太阳风中离子和电子分布函数中各向异性和光束之间的相互作用。 该项目小组将在以前开发的方法基础上，为太阳风中各向异性和束射离子和电子的不稳定阈值制定一个通用理论。 热等离子体色散关系的数值解将使项目小组能够验证分析结果。 项目活动将包括混合模拟，以调查离子不稳定性的非线性演变。 在电子驱动的不稳定性的情况下，一个完整的粒子在细胞的代码将有助于研究小组研究等离子体和激发波的非线性演化。 该项目的理论和数值结果将与太阳风中等离子体和波动特性的观测结果进行比较。 该项目的工作重点将是回答以下关键科学问题：是什么决定了太阳风中各向异性离子和电子束驱动的不稳定性的阈值和非线性演化？ 这个问题的答案是最感兴趣的太阳物理学界，因为物理驱动的太阳风模型关键取决于详细了解相关的微物理过程，调节离子和电子分布功能的非热功能。