Magnetohydrodynamic Turbulence, Charged Particle Transport, and Turbulence in the Extended Solar Atmosphere

磁流体动力湍流、带电粒子输运以及扩展太阳大气中的湍流

• 批准号: 0539995
• 负责人: William Matthaeus
• 金额: $ 45万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-12-15 至 2010-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0539995&HistoricalAwards=false
• 关键词: Magnetohydrodynamic; Turbulence; Charged; Particle; Transport

Turbulence is a complex nonlinear dynamical behavior that we can observe in space plasmas over a wide range of temporal and spatial scales. This proposal offers to advance our understanding of plasma turbulence, a feature of nonlinear plasma electrodynamics that pervades and shapes basic physical phenomena throughout much of the universe. Much of the nonthermal energy stored by space and astrophysical plasmas is found in structures or fluctuations that are well described by magnetohydrodynamic (MHD) models. The solar corona, the solar wind, the magnetosphere, and the interstellar medium may exhibit MHD turbulence, ranging from the largest scales down to the scales at which kinetic dissipation becomes strong. Understanding this MHD turbulence is critical to problems related to coronal heating, the acceleration of the solar wind, distributed heating of the solar wind, mediation of "space weather" by transfer of energy through the heliosphere, and the transport of solar and galactic energetic charged particles throughout the solar system. This proposal continues highly productive projects previously funded by the NSF. The PI intends to further elucidate basic properties of MHD turbulence and transport theories for macroscopic or inhomogeneous processes that include turbulence at smaller scales. He will use test particle theory and simulation to study energetic particle response to turbulence, and adopt an integrated approach using MHD and fluid simulation techniques, transport theory, analytical theories of turbulence and particle diffusion, and related analysis and interpretation of spacecraft observations. In this effort, the PI includes an educational component, supervision and mentorship of junior personnel, and potential contributions to analysis techniques, computational methods, and parallel computing strategies, as well as to industrial and cross disciplinary methodologies and applications.

湍流是一种复杂的非线性动力学行为，我们可以在空间等离子体中观察到广泛的时间和空间尺度。这一提议有助于推进我们对等离子体湍流的理解，这是非线性等离子体电动力学的一个特征，它渗透并塑造了整个宇宙的基本物理现象。空间和天体物理等离子体储存的大部分非热能都存在于磁流体动力学（MHD）模型所描述的结构或波动中。日冕、太阳风、磁层和星际介质可能会出现MHD湍流，范围从最大尺度到动能耗散变强的尺度。了解这种MHD湍流对于日冕加热、太阳风加速、太阳风的分布式加热、通过日光层能量转移的“空间天气”调解以及太阳和银河系高能带电粒子在整个太阳系的传输等问题至关重要。 该提案延续了以前由NSF资助的高生产力项目。PI旨在进一步阐明MHD湍流的基本性质和宏观或非均匀过程的输运理论，包括较小尺度的湍流。他将使用测试粒子理论和模拟来研究高能粒子对湍流的响应，并采用综合方法，使用MHD和流体模拟技术，传输理论，湍流和粒子扩散的分析理论，以及航天器观测的相关分析和解释。在这项工作中，PI包括教育部分，初级人员的监督和指导，以及对分析技术，计算方法和并行计算策略以及工业和跨学科方法和应用的潜在贡献。