This presumably was the first cartoon showing what became the standard thick-target model, exemplified in many cartoons of this Archive (more elegantly, for example, in the Kane-Donnelly cartoon). At this time the thick-target model was already well established for auroral particles, which also precipitate and radiate bremsstrahlung photons. The pioneering observations of both auroral and solar thick targets were made by J.R. Winckler of the University of Minnesota, and his students (notably K.A. Anderson and L.E. Peterson).
Note that this cartoon blithely ignores all hints of MHD effects such as magnetic reconnection, but that it does get some of the interplanetary/solar balance right: note that three arrows point down, and only one up. Most electrons accelerated in the impulsive phase of a flare enter the thick target.
Ed Cliver scanned this historically important but rather inaccessible cartoon - thanks! Please check out his own cartoons (I, II) on the Archive.
August 12, 2008
August 16, 2008