Non-LTE effects on oxygen abundance determinations for solar-type stars
Abstract
Non-LTE effects on oxygen abundance determinations for solar-type stars have been investigated using a model atom of 15 levels plus continuum. The computed equivalent widths of the 777 nm triplet lines in the sun are too large compared to observations, the corresponding LTE values seem to give a better agreement. There are, however, several reasons not to believe that the lines are formed in LTE, and the discrepancy could be due to photospheric inhomogeneities. The implications of the non-LTE effects for oxygen lines on the shape of the galactic (O/Fe)-(Fe/H) relation are discussed.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- May 1991
- Bibcode:
- 1991A&A...245L...9K
- Keywords:
-
- Abundance;
- Atomic Energy Levels;
- Fine Structure;
- Nonequilibrium Thermodynamics;
- Oxygen;
- Stellar Composition;
- Galactic Evolution;
- Line Spectra;
- Metallicity;
- Photosphere;
- Solar Atmosphere;
- Solar Spectra;
- Astrophysics