Heavy-Element Abundances in the Mild Barium Stars Omicron Virginis and 16 Serpentis
Abstract
High-resolution Digicon and Reticon observations are used to determine detailed heavy-element abundances for the mild barium stars O Vir and 16 Ser and a standard star (Ep Vir). A comparison of their heavy-element abundances with those of the classical Ba II stars does not reveal any significant difference in the element-to-element ratios, but the overall enhancements (relative to iron) are smaller in the mild barium stars. This suggests that the mild barium stars originated from the same binary mechanism as the classical Ba II stars. The initial masses of the Ba II stars' former AGB components may have been significantly less than those of normal field red giants. Low masses for the Ba II star progenitors imply that the Ba II stars, while they belong to Population I, are older than the average Population I object, and so account for their observed tendency to be metal deficient.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1986
- DOI:
- 10.1086/164821
- Bibcode:
- 1986ApJ...311..819T
- Keywords:
-
- Abundance;
- B Stars;
- Barium;
- Heavy Elements;
- Stellar Evolution;
- Stellar Spectrophotometry;
- Binary Stars;
- Mass Transfer;
- Red Giant Stars;
- Stellar Mass;
- Astrophysics;
- STARS: ABUNDANCES;
- STARS: BA II;
- STARS: EVOLUTION;
- STARS: INDIVIDUAL CONSTELLATION NAME: O VIRGINIS;
- STARS: INDIVIDUAL CONSTELLATION NAME: 16 SERPENTIS