The temperature of C II emission-line formation regions in cool stars.
Abstract
An investigation has been conducted of the temperature of C II emission-line formation regions in the outer atmospheres of late-type giant and supergiant stars. A distinct dichotomy is seen in the C II lambda 2325/lambda 1335 ratio between coronal and noncoronal stars. It is found that C II emission from noncoronal giant and supergiant stars comes from regions with temperatures of 7000-9000 K, with the mean temperature being approximately 8500 K, whereas the C II emission from coronal stars likely comes from hotter regions. The C II ratio provides a powerful empirical tool for estimating the chromospheric temperatures of cool giants and supergiants.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1984
- DOI:
- 10.1086/184394
- Bibcode:
- 1984ApJ...287L..43B
- Keywords:
-
- Carbon Stars;
- Cool Stars;
- Giant Stars;
- Late Stars;
- Stellar Spectra;
- Stellar Temperature;
- Supergiant Stars;
- Emission Spectra;
- Iue;
- Line Spectra;
- Astrophysics