SHINE: Origin and Evolution of Compressible Fluctuations in the Solar Wind and Their Role in Solar Wind Heating and Acceleration

SHINE：太阳风可压缩脉动的起源和演化及其在太阳风加热和加速中的作用

• 批准号: 2400967
• 负责人: Anna Tenerani
• 金额: $ 46.85万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2400967&HistoricalAwards=false
• 关键词: SHINE; Origin; Evolution; Compressible; Fluctuations

Understanding what leads to coronal heating, solar wind acceleration, and turbulence transport, is key to improve the predictive capabilities of space weather models and, thus, to help preventing catastrophic solar events that can harm astronauts and/or our technological infrastructure. This project will test novel, physics-informed machine learning techniques and, thus, it will provide valuable proof-of-concept methods for the broader plasma physics community (from space physics to astrophysics, to fusion to laser-plasma interactions) and for scientists investigating complex systems. This project will also have significant impact in education, by supporting an early career woman faculty member, postdoctoral researcher, and by providing an opportunity for undergraduate students to be involved in heliophysics research. Interactions between Alfvén and compressible modes can provide an important mechanism to heat the plasma and to enhance the turbulent cascade. However, how these two effects impact the macroscopic properties of the plasma is not yet well understood and, indeed, they are neglected in state-of-the-art global solar wind models. The proposed project will close such a knowledge gap by investigating the role of compressibility, including wave-particle interactions mediated by compressible fluctuations, on solar wind dynamics and thermal properties. By investigating compressible and kinetic effects in the solar wind, and by developing a novel wave-driven solar wind model, this project will provide insights on the role of waves and turbulence in wave-driven wind models. The science objectives of this project are: (1) to characterize the evolution of compressible fluctuations with radial distance and in different types of turbulent solar wind; (2) to determine what phase-space dynamics leads to proton heating and to quantify the heating rate in different types of turbulence (balanced vs. imbalanced); (3) to incorporate kinetic compressible effects into a global wave-driven solar wind model. To achieve our science objectives, we will (1) analyze the radial evolution of fluctuations from Parker Solar Probe, Helios, and Wind data, (2) perform hybrid-PIC numerical simulations and (3) develop a novel global solar wind model based on knowledge-based machine learning methods.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

了解日冕加热、太阳风加速和湍流传输的原因是提高空间天气模型预测能力的关键，从而有助于防止可能伤害宇航员和/或我们的技术基础设施的灾难性太阳事件。测试新颖的、基于物理的机器学习技术，因此，它将为更广泛的等离子体物理学界（从空间物理学到天体物理学，从聚变到激光等离子体相互作用）和科学家提供有价值的概念验证方法该项目还将通过支持早期职业女教员、博士后研究员以及为本科生提供参与太阳物理学研究的机会，对教育产生重大影响。加热等离子体和增强湍流级联的重要机制然而，这两种效应如何影响等离子体的宏观特性尚不清楚，事实上，它们在最先进的全球太阳风中被忽视了。拟议的项目将通过研究可压缩性（包括可压缩涨落介导的波粒相互作用）对太阳风动力学和热特性的作用来缩小这一知识差距，并通过研究太阳风中的可压缩和动力学效应来弥补这一知识差距。通过开发一种新型的波浪驱动太阳风模型，该项目将深入了解波浪和湍流在波浪驱动风模型中的作用。该项目的科学目标是：（1）表征可压缩涨落随径向距离的演变。并且在不同类型的湍流太阳风；（2）相空间动力学导致质子加热并量化不同类型湍流（平衡与不平衡）的加热速率；（3）确定全球波驱动太阳能的动力学可压缩效应为了实现我们的科学目标，我们将 (1) 分析帕克太阳探测器、Helios 和风数据的波动的径向演化，(2) 执行混合 PIC 数值模拟，以及 (3) 开发一种新颖的模型。基于基于知识的机器学习方法的全球太阳风模型。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。