Storm‐time broadband electromagnetic field variations along the interface between the dipolar field of the Earth's inner‐magnetosphere and the stretched fields of the plasma‐sheet are decomposed as a superposition of fluid‐kinetic modes. Using model eigen‐vectors operating on the full set of Van Allen Probes fields measurements it is shown how these variations are composed of a broad spectrum of dispersive Alfvén waves with significant spectral energy densities in the fast and slow modes over scales extending into the kinetic range. These modes occupy volumes in
Three‐dimensional X‐line spreading is important for the coupling between global dynamics and local kinetic physics of magnetic reconnection. Using large‐scale 3‐D particle‐in‐cell simulations, we investigate the spreading of the X‐line out of the reconnection plane under a strong guide field in asymmetric reconnection. The X‐line spreading speed depends strongly on the equilibrium current sheet thickness. In a simulation with a thick, ion‐scale equilibrium current sheet (CS), the X‐line spreads at the ambient species drift speeds, which are significantly lower than the Alfvén speed based on the guide field
- NSF-PAR ID:
- 10374426
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 125
- Issue:
- 2
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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