Further measurements of emission line profiles in the solar ultraviolet spectrum.
Abstract
A further flight of a high resolution echelle spectrograph has been carried out on a Skylark rocket to measure solar line profiles in the region 1400-2200 A. Improvements in reflective coatings and better thermal stability resulted in an increase in both the number and quality of profiles recorded. Microdensitometer traces for 37 emission lines are presented. Analysis of the profiles leads to a nonthermal mechanical velocity component which increases with temperature over the range 6,000 to 100,000 K, always remaining subsonic. Interpretations are considered in terms of a progressive mechanical energy flux to the corona. These include acoustic and MHD modes for both spherically symmetric and network models of the atmosphere.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- June 1975
- DOI:
- 10.1093/mnras/171.3.697
- Bibcode:
- 1975MNRAS.171..697B
- Keywords:
-
- Emission Spectra;
- Line Spectra;
- Solar Spectra;
- Ultraviolet Spectra;
- Magnetohydrodynamic Waves;
- Microdensitometers;
- Rocket Sounding;
- Sound Waves;
- Spectral Line Width;
- Solar Physics