Non-linear physics of the solar wind and impacts at earth

天体物理等离子体被观察到作为有效的粒子加速器，将电磁场能量转换为粒子能量和热量。完全非线性的基本等离子体过程，如重连，冲击和湍流被观察到加速等离子体，但这些过程尚未得到充分理解。悬而未决的问题包括太阳风是如何被加热的，这是否是一个普遍机制的结果，以及在没有碰撞的情况下，冲击如何增加熵。太阳风和行星冲击为这些现象提供了一个独特的诊断自然观测站：从亚秒级到太阳周期的时间尺度都可以进行现场卫星观测。太阳风的物理学不仅具有基本的物理意义，而且对于理解空间天气对地球的影响至关重要。该项目涉及对这些数据集的定量分析，以进一步了解这些非线性现象的物理学，并量化它们在等离子体加热和粒子加速中的作用。对地球地磁响应的数据分析，以及对太阳风的数据分析，将把这些结果与我们对空间天气的理解联系起来。

Astrophysical plasmas are observed to act as efficient particle accelerators, converting electromagnetic field energy into particle energy and heat. Fully non-linear fundamental plasma processes such as reconnection, shocks and turbulence are observed to accelerate the plasma, but these processes are yet to be fully understood. Open questions include how the solar wind is heated and whether this is the result of a universal mechanism, and how shocks increase entropy in the absence of collisions. The solar wind and planetary shocks offer a uniquely diagnosed natural observatory for these phenomena: in-situ satellite observations are available from sub-second timescales to that of the solar cycle. As well as being of fundamental physical interest, the physics of the solar wind is central to understanding space weather impacts on earth. This project involves quantitative analysis of these datasets in order to further our understanding of the physics of these nonlinear phenomena and to quantify their role in plasma heating and particle acceleration. Data analysis of the geomagnetic response at earth, alongside that of the solar wind, will connect these results into our understanding of space weather.