Daniel Verscharen, Kristopher G. Klein, Bennett A. Maruca
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引用次数: 198
Abstract
The solar wind is a magnetized plasma and as such exhibits collective plasma behavior associated with its characteristic spatial and temporal scales. The characteristic length scales include the size of the heliosphere, the collisional mean free paths of all species, their inertial lengths, their gyration radii, and their Debye lengths. The characteristic timescales include the expansion time, the collision times, and the periods associated with gyration, waves, and oscillations. We review the past and present research into the multi-scale nature of the solar wind based on in-situ spacecraft measurements and plasma theory. We emphasize that couplings of processes across scales are important for the global dynamics and thermodynamics of the solar wind. We describe methods to measure in-situ properties of particles and fields. We then discuss the role of expansion effects, non-equilibrium distribution functions, collisions, waves, turbulence, and kinetic microinstabilities for the multi-scale plasma evolution.
期刊介绍:
Living Reviews in Solar Physics, a platinum open-access journal, publishes invited reviews covering research across all areas of solar and heliospheric physics. It distinguishes itself by maintaining a collection of high-quality reviews regularly updated by the authors. Established in 2004, it was founded by the Max Planck Institute for Solar System Research (MPS). "Living Reviews®" is a registered trademark of Springer International Publishing AG.