Study of microturbulence from equivalent widths of moderate and moderately strong Fe I lines.
Abstract
Equivalent widths of 25 weak and moderately strong Fe I Fraunhofer lines are analyzed using data from center-limb observations of the solar disk. An iron abundance with a logarithm of 7.04 is derived from the weak lines. Microturbulent velocity fields are investigated by employing the abundance values derived from moderately strong lines. A model of quasi-isotropic microturbulent velocity smoothly increasing with height from 0.6 km/s to 1.5 km/s (mean value, 1.1 km/s) over the depth range between 100 and 600 km is obtained for a specified photospheric model. It is concluded that microturbulent velocity can be determined only by analyzing absolute values of equivalent line widths and that the microturbulent-velocity model can be improved by analyzing lines formed at different depths.
- Publication:
-
Astrometriia i Astrofizika
- Pub Date:
- 1976
- Bibcode:
- 1976AAfz...30...14G
- Keywords:
-
- Fraunhofer Lines;
- Iron;
- Solar Spectra;
- Spectral Line Width;
- Turbulent Flow;
- Abundance;
- Atmospheric Models;
- Flow Velocity;
- Photosphere;
- Velocity Distribution;
- Solar Physics