Plasmoids in Reconnecting Current Sheets: Solar and Terrestrial Contexts Compared |
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Steven R Cranmer Submitted: 2008-09-23 10:41
Magnetic reconnection plays a crucial role in violent energy conversion
occurring in the environments of high electrical conductivity, such as
the solar atmosphere, magnetosphere, and fusion devices. We focus on the
morphological features of the process in two different environments, the
solar atmosphere and the geomagnetic tail. In addition to indirect evidence
that indicates reconnection in progress or having just taken place, such as
auroral manifestations in the magnetosphere and the flare loop system in
the solar atmosphere, more direct evidence of reconnection in the solar
and terrestrial environments is being collected. Such evidence includes
the reconnection inflow near the reconnecting current sheet, and the
outflow along the sheet characterized by a sequence of plasmoids. Both
turbulent and unsteady Petschek-type reconnection processes could account
for the observations. We also discuss other relevant observational
consequences of both mechanisms in these two settings. While on face
value, these are two completely different physical environments, there
emerge many commonalities, for example, an Alfvén speed of the same
order of magnitude, a key parameter determining the reconnection rate.
This comparative study is meant as a contribution to current efforts
aimed at isolating similarities in processes occurring in very
different contexts in the heliosphere, and even in the universe.
Authors: J. Lin, S. R. Cranmer, and C. J. Farrugia
Projects: None
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Publication Status: JGR, in press for special NESSC section on Comparative Aspects of Magnetic Reconnection.
Last Modified: 2008-09-23 18:09
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