New Theory and Applications with the Regularized Kappa-Distribution

正则化 Kappa 分布的新理论和应用

• 批准号: 511321267
• 负责人: Privatdozent Dr. Horst Fichtner
• 金额: --
• 依托单位: Observatoire de Paris
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/511321267?language=en
• 关键词: New; Theory; Applications; Regularized; Kappa

With this project we will advance the non-equilibrium plasma theory and corresponding specific applications by employing the Regularized Kappa Distribution (RKD) that was introduced recently for a realistic treatment and interpretation of suprathermal particle populations and their implications in various astrophysical systems. This RKD allows one to overcome a series of critical limitations and deficiencies of the standard Kappa distribution (SKD) mainly determined by the diverging velocity moments, a non-extensive entropy as well as undesired contributions of unphysical superluminal particles. The new RKD concept motivates systematic explorations of its consequences in kinetic as well as fluid theory and corresponding studies of astrophysical plasma systems on small and large scales. Consequently, the main objective of the proposed project is to develop new theoretical approaches based on the RKD and to apply them to non-equilibrium multi-scale plasmas, with an emphasis on the best observed astrophysical system, i.e., the heliosphere. This objective is explicitly formulated with two scientific key questions, one of which is addressing kinetic theory and the other the fluid theory: (Q1) What are the implications of using the RKD in the kinetic theory for the properties of plasma waves and instabilities? (Q2) How can a fluid theory based on the RKD be derived and applied to nonthermal astrophysical systems? The answer to the first question will clarify, by means of analytical and numerical modelling, the consequences of using the RKD for plasma waves on small, i.e. kinetic scales. That to the second question will establish a consistent quantitative treatment of the plasma dynamics on large, i.e. fluid scales. The modelling and its assessment with data will be realized by the fulfillment of the following three tasks: (i) the development of the kinetic theory for the RKD and its application to particle populations in the solar wind plasma, (ii) the use of macroscopic moments of the RKD and appropriate source terms for mass, momentum and energy to derive MHD-like fluid equations and their application, and (iii) the validation of the kinetic and fluid results with spacecraft data. With the corresponding analytical and numerical studies we will not only deepen the understanding of the physical relevance of the RKD and its significance for astrophysical plasma systems, in particular the solar wind, but also establish, for the first time, a kinetic and a fluid description of nonthermal astrophysical plasmas that are fully consistent with each other. The validation of the theory and the modelling will be made on the basis of various spacecraft data, particularly from the recently launched NASA mission Parker Solar Probe and the forthcoming ESA mission Solar Orbiter.

通过这个项目，我们将推进非平衡等离子体理论和相应的具体应用，采用正则化卡帕分布（RKD），这是最近推出的超热粒子种群及其在各种天体物理系统中的影响的现实治疗和解释。这个RKD允许一个克服一系列的关键限制和缺陷的标准Kappa分布（SKD）主要由发散的速度矩，非广延熵以及非物理超光速粒子的不希望的贡献。新的RKD概念激发了对其在动力学和流体理论中的后果的系统探索，以及对小尺度和大尺度天体物理等离子体系统的相应研究。因此，拟议项目的主要目标是在RKD的基础上开发新的理论方法，并将其应用于非平衡多尺度等离子体，重点是观测到的最佳天体物理系统，即，日光层这一目标明确制定了两个科学的关键问题，其中之一是解决动力学理论和其他流体理论：（Q1）在动力学理论中使用RKD的等离子体波和不稳定性的性质有什么影响？(Q2)基于RKD的流体理论如何导出并应用于非热天体物理系统？第一个问题的答案将澄清，通过分析和数值模拟，使用RKD的等离子体波小，即动力学尺度的后果。这对第二个问题将建立一个一致的定量处理等离子体动力学在大，即流体尺度。建模及其数据评估将通过完成以下三项任务来实现：（i）RKD的动力学理论的发展及其在太阳风等离子体中粒子群的应用，（ii）使用RKD的宏观矩和质量、动量和能量的适当源项来导出MHD类流体方程及其应用，以及（iii）用航天器数据验证动力学和流体结果。 通过相应的分析和数值研究，我们不仅将加深对RKD的物理相关性及其对天体物理等离子体系统，特别是太阳风的意义的理解，而且还将首次建立相互完全一致的非热天体物理等离子体的动力学和流体描述。将根据各种航天器数据，特别是最近发射的美国航天局使命帕克太阳探测器和即将发射的欧空局使命太阳轨道器的数据，对理论和模型进行验证。