Physical parameters of solar H-alpha absorption features derived with the cloud model
Abstract
Observations of a fibril region and of an arch filament region obtained by the Multichannel Subtractive Double Pass Spectrograph (MSDP) operating in H-alpha at the Pic du Midi Observatory are presented. Intensity fluctuations and Doppler shift velocities were derived over two dimensional fields of view. The observed contrast profiles have been matched with theoretical contrast profiles based on the cloud model which has four parameters: the line-of-sight velocity, the source function, the optical depth, and the Doppler width. Contour maps and histograms of the 4 parameters were made for these regions, and a comparison of the velocities given by 3 different methods (cloud model, Doppler shift, and the '3-optical depths' method of Mein and Mein, 1988) is made.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- April 1990
- Bibcode:
- 1990A&A...230..200A
- Keywords:
-
- Astronomical Models;
- Chromosphere;
- H Alpha Line;
- Solar Activity;
- Solar Physics;
- Energy Transfer;
- Line Of Sight;
- Topography;
- Solar Physics