CAOSP abstracts, Volume: 28, No.: 3, year: 1999
- Author(s): KOUTCHMY, S.
- Journal: Contributions of the Astronomical Observatory Skalnate Pleso,
vol. 28, no. 3, p. 173-186.
- Date: 03/1999
- Title: Eclipse 99 -- High Resolution Imaging: Why and how?
- Keyword(s): ECLIPSE, CORONA, FAINT STRUCTURE
- Pages: 173 -- 186
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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