行星际太阳风研究中的几个基本问题

This proposal focuses on several fundamental problems related to magnetic reconnection in the study of solar wind: the origin and evolution of Bz (the south component of interplanetary magnetic field); turbulent solar wind and turbulent magnetic reconnection associated with the heliospheric current sheet; preliminary analyses of quasi-elastic dynamic interactions between the solar wind and the magnetosphere; and diagnoses on the mechanism of interplanetary magnetic reconnection. The scientific objectives are：to reproduce the magnetic structures inside the solar eruptions, to understand the origin and evolution of Bz in interplanetary space so as to establish the related forecasting model; to reveal the influence of magnetic reconnection on the dissipation range of solar wind turbulence and develop new analyzing methods; to analyze the quasi-elastic dynamic compression and relaxation of the magnetopause and investigate the possibility of constructing the relevant key parameters such as coefficients of elasticity and restitution, and intrinsic frequency of the quasi-elastic dynamic magnetosphere; to comparatively study the current triggering mechanism of magnetic reconnection with its capability of diagnosing interplanetary magnetic reconnection and explore the applicability of the concept of magnetic reconnection under different solar wind conditions. By investigating these problems in different physical regions, on various temporal and spatial scales, and of diverse physical processes, the proposal is to achieve significant breakthroughs in several fundamental problems given above, and enhance our knowledge of the physical nature of magnetic reconnection.

项目关注行星际太阳风研究中与磁重联问题有一定关系的几个基本问题：行星际磁场南向分量Bz的起源与演化；湍动太阳风与湍动磁重联关系；太阳风与地球磁层相互作用的准弹性动力学行为初探；日球电流片磁重联发生机理的诊断。主要科学目标是重现太阳活动抛射物磁结构，了解Bz在行星际空间的演化过程，分析磁重联的影响；揭示磁重联对湍动太阳风耗散区特性的影响，发展新的分析方法；分析地球磁层顶压缩-恢复运动过程的准弹性动力学行为；尝试构建基本参数,如准弹性系数、恢复系数和描述磁层准弹性系统的本征频谱特征等；比对研究现今磁重联发生机理应用于行星际日球电流片磁重联的诊断，探索磁重联概念的适用性。本项目从不同物理区域、不同尺度结构、不同物理状态的多视角来研究上述太阳风问题，预期项目将在所研究的几个基本问题的难点突破方面取得重要新进展，也会增进对磁“重联”物理本质的新认识。

本项目以磁场重联在太阳日冕、湍动太阳风的表现和关键物理过程中的作用、1AU处行星际磁场南向磁场分量的数值预报方法为研究主线，以探索行星际磁重联区域物理特性、发展磁重联数值模拟技术为重点。通过数据模拟和观测分析，本项目主要研开展了以下工作：磁云边界层前的类Petschek磁重联喷流区慢激波的首次观测，磁云边界层和鞘区中的磁重联加热效应；研究了磁层顶准弹性动力学过程；数据驱动的太阳活动源区演化和连续同源太阳爆发现象；内凹的磁层顶处反常的磁场梯度事件，磁层顶日下点附近的过冲磁场结构，地球辐射带对太阳风扰动结构的响应，电子回旋谐波的上升调结构；行星际太阳风和扰动传播的高精度建模，CME驱动的激波特性和CME形态演化的模拟研究，行星际磁场南向分量的数值建模预报。项目组发表科学论文65篇，其中SCI论文59篇。