Hnat B, Chapman S C, Watkins N W
CFSA, Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom.
CFSA, Physics Department, University of Warwick, Coventry CV4 7AL, United Kingdom Grantham Research Institute on Climate Change and the Environment, LSE, London WC2A 2AE, United Kingdom and School of Engineering and Innovation, The Open University, Milton Keynes MK7 6AA, United Kingdom.
Phys Rev Lett. 2021 Mar 26;126(12):125101. doi: 10.1103/PhysRevLett.126.125101.
Multipoint in situ observations of the solar wind are used to identify the magnetic topology and current density of turbulent structures. We find that at least 35% of all structures are both actively evolving and carrying the strongest currents, actively dissipating, and heating the plasma. These structures are comprised of ∼1/5 3D plasmoids, ∼3/5 flux ropes, and ∼1/5 3D X points consistent with magnetic reconnection. Actively evolving and passively advecting structures are both close to log-normally distributed. This provides direct evidence for the significant role of strong turbulence, evolving via magnetic shearing and reconnection, in mediating dissipation and solar wind heating.
利用太阳风的多点原位观测来识别湍流结构的磁拓扑和电流密度。我们发现,所有结构中至少35%既在积极演化,又携带最强电流、积极耗散并加热等离子体。这些结构由约1/5的三维等离子体团、约3/5的通量绳和约1/5与磁重联一致的三维X点组成。积极演化和被动平流的结构都接近对数正态分布。这为强湍流通过磁剪切和重联演化在介导耗散和太阳风加热中所起的重要作用提供了直接证据。