MANGANESE ABUNDANCES IN THE GLOBULAR CLUSTER {omega} CENTAURI
- National Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ, 85719 (United States)
- Max-Planck Institute for Astrophysics, Karl-Schwarzschild Str. 1, 85741 Garching (Germany)
- Department of Physics and Astronomy and Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States)
- University of Texas, 1 University Station, C1400, Austin, TX 78712 (United States)
We present manganese abundances in 10 red giant members of the globular cluster {omega} Centauri; eight stars are from the most metal-poor population (RGB MP and RGB MInt1) while two targets are members of the more metal-rich groups (RGB MInt2 and MInt3). This is the first time Mn abundances have been studied in this peculiar stellar system. The LTE values of [Mn/Fe] in {omega} Cen overlap those of Milky Way stars in the metal-poor {omega} Cen populations ([Fe/H] {approx}-1.5 to -1.8), however unlike what is observed in Milky Way halo and disk stars, [Mn/Fe] declines in the two more metal-rich RGB MInt2 and MInt3 targets. Non-LTE calculations were carried out in order to derive corrections to the LTE Mn abundances. The non-LTE results for {omega} Cen in comparison with the non-LTE [Mn/Fe] versus [Fe/H] trend obtained for the Milky Way confirm and strengthen the conclusion that the manganese behavior in {omega} Cen is distinct. These results suggest that low-metallicity supernovae (with metallicities {<=} -2) of either Type II or Type Ia dominated the enrichment of the more metal-rich stars in {omega} Cen. The dominance of low-metallicity stars in the chemical evolution of {omega} Cen has been noted previously in the s-process elements where enrichment from metal-poor asymptotic giant branch stars is indicated. In addition, copper, which also has metallicity-dependent yields, exhibits lower values of [Cu/Fe] in the RGB MInt2 and MInt3 {omega} Cen populations.
- OSTI ID:
- 21452867
- Journal Information:
- Astrophysical Journal, Vol. 717, Issue 1; Other Information: DOI: 10.1088/0004-637X/717/1/333; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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