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arXiv · 1003.4758

Reconnection Outflows and Current Sheet Observed with Hinode/XRT in the 2008 April 9 "Cartwheel CME" Flare

Sabrina L. Savage·David E. McKenzie·Katharine K. Reeves·Terry G. Forbes·Dana W. Longcope
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Abstract

Supra-arcade downflows (SADs) have been observed with Yohkoh/SXT (soft X-rays (SXR)), TRACE (extreme ultra-violet (EUV)), SoHO/LASCO (white light), SoHO/SUMER (EUV spectra), and Hinode/XRT (SXR). Characteristics such as low emissivity and trajectories which slow as they reach the top of the arcade are consistent with post-reconnection magnetic flux tubes retracting from a reconnection site high in the corona until they reach a lower-energy magnetic configuration. Viewed from a perpendicular angle, SADs should appear as shrinking loops rather than downflowing voids. We present XRT observations of supra-arcade downflowing loops (SADLs) following a coronal mass ejection (CME) on 2008 April 9 and show that their speeds and decelerations are consistent with those determined for SADs. We also present evidence for a possible current sheet observed during this flare that extends between the flare arcade and the CME. Additionally, we show a correlation between reconnection outflows observed with XRT and outgoing flows observed with LASCO.

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Sabrina L. Savage, David E. McKenzie, Katharine K. Reeves, Terry G. Forbes, Dana W. Longcope. 2010-08-14. Reconnection Outflows and Current Sheet Observed with Hinode/XRT in the 2008 April 9 "Cartwheel CME" Flare. https://doi.org/10.1088/0004-637x%2F722%2F1%2F329

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