Data-validated, Self-consistent Modelling of Turbulence and Particle Transport in the Heliosphere

在这个为期3年的研究项目中，我们打算继续两位申请者H. Fichtner（鲁尔-波亨大学）和B. Heber （christian - albrecht - Kiel大学）的研究小组与ms . Potgieter（西北大学，Campus Potchefstroom，南非）在“日球层磁场结构中的粒子输移”主题上的成功合作。考虑到即将发射的太阳轨道器（Solar Orbiter）、太阳探测器Plus (Solar Probe Plus)（2018年发射）和雷神（THOR）（2026年发射）将观测高能粒子和太阳风等离子体，这项研究仍然非常及时。要全面理解预期的测量结果，关键在于同时模拟动态等离子体中的湍流和高能粒子的输运。为了改进以前的方法，我们将首次应用一套尽可能自洽的模型，并具有与三维多点航天器数据进行详细比较的新颖方面，真实的内部（太阳）边界条件，并明确考虑日球层磁场波动的板状和准二维分量。这将使我们能够解决以下核心科学问题：当前最先进的动力学输运、磁流体动力学和湍流演化模型是否可以用于解释随时间变化的三维多点航天器数据？为了回答这个问题，一方面，我们将利用高分辨率磁场和等离子体测量作为输入，同时模拟高能粒子输运与太阳风动力学以及瞬态和周期性结构中的湍流演化。另一方面，我们将研究航天器在太阳活动周期的不同阶段测量瞬态和循环结构以及太阳高能粒子事件的特定时期，以验证组合模型并约束模型参数。通过这种方式，我们将确定传输模型及其参数，这些模型和参数允许解释来自不同航天器的高能粒子数据，并定义其合理性的标准。

With the proposed 3-year research project we intend to continue the successful collaboration between the research groups of the two applicants H. Fichtner (Ruhr-Universitaet Bochum) and B. Heber (Christian-Albrechts-Universitaet zu Kiel) with M.S. Potgieter (North-West University, Campus Potchefstroom, South Africa) on the topic of `particle transport in heliospheric magnetic field structures'. The research is still very timely in view of the upcoming space missions Solar Orbiter, Solar Probe Plus (to be launched in 2018), and THOR (2026) that will observe energetic particles and the solar wind plasma. A key for a comprehensive understanding of the expected measurements will be the simultaneous modelling of turbulence in the dynamic plasma and of energetic particle transport. In improvement of previous approaches we will, for the first time, apply a model suite being self-consistent as far as possible and featuring the novel aspects of detailed comparisons with three-dimensional multi-point spacecraft data, realistic inner (solar) boundary conditions, and an explicit consideration of the slab and quasi-two-dimensional components of the fluctuations of the heliospheric magnetic field. This will enable us to address the following central science question: can current combined state-of-the-art kinetic transport, magnetohydrodynamic, and turbulence evolution models be used to explain time-dependent, three-dimensional multi-point spacecraft data? In order to answer this question we will, on the one hand, model the energetic particle transport simultaneously with the solar wind dynamics and the turbulence evolution in transient as well as recurrent structures using high-resolution magnetic field and plasma measurements as input. On the other hand, we will investigate particular periods of spacecraft measurements of transient and recurrent structures as well as solar energetic particle events during different phases of the solar activity cycle in order to validate the suite of combined models and to constrain model parameters. This way, we will determine the transport models and their parameters that allow to explain energetic particle data from different spacecraft and define criteria for their plausibility.