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arXiv · 1610.06905

Observations of the Formation, Development, and Structure of a Current Sheet in an Eruptive Solar Flare

Daniel B. Seaton·Allison E. Bartz·Jonathan M. Darnel
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Abstract

We present AIA observations of a structure we interpret as a current sheet associated with an X4.9 flare and coronal mass ejection that occurred on 2014~February~25 in NOAA Active Region 11990. We characterize the properties of the current sheet, finding that the sheet remains on the order of a few thousand km thick for much of the duration of the event and that its temperature generally ranged between $8-10\,\mathrm{MK}$. We also note the presence of other phenomena believed to be associated with magnetic reconnection in current sheets, including supra-arcade downflows and shrinking loops. We estimate that the rate of reconnection during the event was $M_{A} \approx 0.004-0.007$, a value consistent with model predictions. We conclude with a discussion of the implications of this event for reconnection-based eruption models.

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Daniel B. Seaton, Allison E. Bartz, Jonathan M. Darnel. 2016-10-21. Observations of the Formation, Development, and Structure of a Current Sheet in an Eruptive Solar Flare. https://doi.org/10.3847/1538-4357%2F835%2F2%2F139

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