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arXiv · 2607.03697

SADCat: A Catalog of Supra-Arcade Downflow Events in Solar Flares

Trestan F. Simon·Ryan J. French
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Abstract

Supra-arcade downflows (SADs) are sunward-traveling features routinely observed in hot fan structures above magnetic loop arcades during eruptive solar flares. We manually compiled a catalog (SADCat) of 178 SAD-productive flares imaged by the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO) during solar cycle 24 as a resource for the wider solar flare community. We conducted a preliminary analysis of the SADCat, comparing the flare X-ray and CME properties between eruptive solar flares with and without SADs. We found that peak GOES X-ray flux, flare duration, CME speed, and CME mass have a strong influence on whether a flare produces visible SADs, whereas flare impulsivity and CME acceleration have little effect.

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Trestan F. Simon, Ryan J. French. 2026-07-04. SADCat: A Catalog of Supra-Arcade Downflow Events in Solar Flares. https://doi.org/10.1007/s11207-026-02708-z

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