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

TL;DR

This paper reports on XRT observations of supra-arcade downflowing loops during the 2008 April 9 flare, providing insights into reconnection outflows, current sheet structures, and their relation to CME dynamics.

Contribution

It presents new XRT observations of SADLs, evidence for a current sheet during the flare, and links between reconnection outflows and CME flows, enhancing understanding of flare reconnection processes.

Findings

SADLs' speeds and decelerations match SADs.

Evidence of a current sheet during the flare.

Correlation between reconnection outflows and CME flows.

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.