From Red Giant to Planetary Nebula: Dust, Asymmetry, and Polarization
Abstract
The polarization characteristics of stars in the stages of evolution from red giant to planetary nebula are investigated. Polarization is found to be a characteristic of the majority of these stars. The maximum observed polarization increases with age as the star evolves up the asymptotic giant branch (AGB) to the protoplanetary nebula phase, where the polarization reaches a maximum. The polarization then decreases as the star further evolves into a planetary nebula. These results indicate that aspherical mass loss is likely to be a continual feature of the late stages of stellar evolution, maintaining a clear continuity throughout the life of a star from the moment it first develops a measurable dust shell. The aspherical morphology seen in planetary nebulae has its origin in an intrinsic property of the star that is present at least as early as its arrival at the base of the AGB.
- Publication:
-
The Astronomical Journal
- Pub Date:
- May 1991
- DOI:
- 10.1086/115801
- Bibcode:
- 1991AJ....101.1735J
- Keywords:
-
- Cosmic Dust;
- Planetary Nebulae;
- Polarization Characteristics;
- Red Giant Stars;
- Stellar Evolution;
- Asymptotic Giant Branch Stars;
- Infrared Astronomy Satellite;
- Polarimetry;
- Stellar Mass Ejection;
- Stellar Models;
- Astrophysics;
- STARS: RED GIANTS;
- NEBULAE: PLANETARY