Comparison Between Coronal and In Situ Plasma Properties Over The Solar Cycle
Abstract
The Ultraviolet Coronagraph Spectrometer (UVCS) on SOHO has made detailed observations of coronal streamers in the extended corona (1.5 Ro < r < 10 Ro) for almost a complete solar cycle. Measurements of ultraviolet line profiles and intensities and polarized white light intensities are used to determine plasma parameters (proton and ion temperatures, electron densities, and ion outflow speeds) for these large scale coronal structures. In this paper we compare the variations in streamer properties obtained in the extended corona with the properties found in the solar wind at 1 AU. Solar wind velocities and densities derived from in situ data are used for comparisons. Such comparisons may be used to distinguish between solar wind variations due to changes in physical parameters of streamers at the Sun as opposed to changes in flow geometry. This work was supported by NASA grants NAG5-12781 and NNG05GG38G to the Smithsonian Astrophysical Observatory.
- Publication:
-
AAS/Solar Physics Division Meeting #37
- Pub Date:
- June 2006
- Bibcode:
- 2006SPD....37.1004S