CAOSP abstracts, Volume: 28, No.: 3, year: 1999


Abstract: A very large white-light (W-L) coronal flux is made available during total eclipses. High speed analysis of very fine-scale structures of the magnetically dominated solar atmosphere is then possible, including the deeply seeded sources of the solar mass loss. Additional observations of both the disk and of the more outer corona should be simultaneously collected from space, using the SOHO and the Yohkoh missions to complement the data. The most optimum eclipse studies should concentrate on the intermediate corona where acceleration processes are taking place. MHD waves, including magneto-acoustic propagating waves and standing loop-resonance waves are everywhere present with rather short periods. W-L fine imaging at high-speed and high signal-noise ratio is needed to avoide the overlapping problem and measure their magnitude. Ubiquitous plasmoid-like objects are also produced in this region near the temperature maximum and they need a special attention. They are the rather privileged site where both the radiative cooling and the magnetic dissipation mechanisms are occuring. Eclipses are good opportunities to look at the dynamics of coronal ejecta. At larger scale, sharp edges of streamers and plumes can be used to deduce a 3-D view of the coronal neutral sheets, provided pictures taken at several hours interval are made available along the path of the totality. Both the quasi-rigid rotation and the more subtil outward motions of coronal material are then evidenced, giving a good tool to study the origine of the slow wind.

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