Non-Gaussian Line Profiles in a Large Solar Flare Observed on 2006 December 13

It has long been known to Hα observers that the outer edges of the flare ribbons, in a typical double-ribbon flare geometry, exhibit weird line profiles. This has been one of the most important pieces of evidence supporting the CSHKP large-scale reconnection picture of solar flares, since the only credible mechanism ever proposed is in fact flux transfer across a separatrix. This cartoon illustrates that, in the context of an Fe XIV line. As often happens this result is treated here as a new discovery, but the Archivist is sure that you can see the same physics in many earlier descriptions. Still, in spite of the possibly faulty scholarship in this paper, it is good to have this most important fact captured in a cartoon.