Volume 382, Number 1, JanuaryIV 2002
|Page(s)||328 - 341|
|Section||Planets and planetary systems|
|Published online||15 January 2002|
The inner solar corona seen by SUMER, LASCO/C1, and EIT: Electron densities and temperatures during the rise of the new solar cycle
Max-Planck-Institut für Aeronomie, Max-Planck-Straße 2, 37191 Katlenburg-Lindau, Germany
2 Naval Research Laboratories, 4555 Overlook Ave., SW, Washington, DC 20375, USA
Corresponding author: K. Wilhelm, firstname.lastname@example.org
Accepted: 9 November 2001
Detailed investigations of the corona and the source regions of the solar wind have become possible with spectroscopic and imaging instruments on the Solar and Heliospheric Observatory (SOHO). We present observations in the extreme ultraviolet (EUV), pertinent to the generation of the slow solar wind, which were obtained by the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrograph and by the Extreme-ultraviolet Imaging Telescope (EIT) in early 1998 under relatively quiet solar conditions, but with several active regions of the new solar cycle present. At the same time, forbidden iron lines in the visible were observed by the Large-Angle Spectroscopic Coronagraph (LASCO/C1). We study, in particular, the plasma parameters and the spatial structures of the low-altitude streamer regions, and find an electron density of cm-3 at 5 Mm above the equatorial limb for the coronal plasma, and cm-3 for the plasma at transition-region temperatures. High-temperature regions have been found at mid-latitudes with electron temperatures of K at heights of about 80 Mm and lower temperatures near the equator.
Key words: Sun: atmosphere / Sun: transition region / Sun: corona / Sun: UV radiation
© ESO, 2002
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.