The boundary line in the H-R diagram for stellar chromospheres and the theory of convection.
Abstract
Ultraviolet emission-line spectra of A, F, and early G stars have been observed with the International Ultraviolet Explorer. For supergiants, classical chromospheric and transition-layer emission is seen only on the red side of the Cepheid instability strip. For luminosity classes III-V, chromospheric emission can be detected for spectral types F2 and later. For none of the A stars was normal chromospheric emission detected, regardless of their rotational velocities or peculiarities (i.e., Am or Ap).
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1980
- DOI:
- 10.1086/157774
- Bibcode:
- 1980ApJ...236..560B
- Keywords:
-
- Chromosphere;
- Convection;
- Emission Spectra;
- Hertzsprung-Russell Diagram;
- Stellar Magnitude;
- Stellar Spectra;
- Ultraviolet Spectra;
- A Stars;
- G Stars;
- Iue;
- Line Spectra;
- Stellar Luminosity;
- Stellar Rotation;
- Supergiant Stars;
- Astrophysics