Ionization conditions in the expanding envelopes of O and B stars.
Abstract
Cool and hot models for the expanding envelopes of early stars are discussed with reference to the abundance of O VI, N V, and Si IV ions. The cool models are rejected on the grounds that simple radiative ionization would not be sufficient to account for the degree of ionization measured. Instead, a model is proposed in which the envelopes themselves have temperatures ranging from tens to hundreds of thousands of degrees Kelvin. Tables are given comparing ion abundance against stellar envelope parameters. The electron density and optical properties of the envelopes are also considered.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1978
- DOI:
- 10.1086/155807
- Bibcode:
- 1978ApJ...219..504L
- Keywords:
-
- B Stars;
- O Stars;
- Stellar Envelopes;
- Stellar Mass Ejection;
- Stellar Models;
- Stellar Winds;
- Boundary Value Problems;
- Early Stars;
- Gas Ionization;
- Radiation Pressure;
- Astrophysics;
- B Stars:Envelopes;
- Envelopes:O Stars;
- Ionization:Stellar Envelopes