The extended star formation history of ω Centauri ⋆

Content Provider	Semantic Scholar
Author	Hilker, Michael Kayser, Andrea Richtler, Tom Willemsen, Philip
Copyright Year	2004
Abstract	For the first time, the abundances of a large sample of subgiant and turn-off region stars in ω Centauri have been measured, the data base being medium resolution spectroscopy from FORS2 at the VLT. Absolute iron abundances were derived for ∼400 member stars from newly defined line indices with an accuracy of ±0.15 dex. The abundances range between −2.2 < [Fe/H] < −0.7 dex, resembling the large metallicity spread found for red giant branch stars. The combination of the spectroscopic results with the location of the stars in the colour magnitude diagram has been used to estimate ages for the individual stars. Whereas most of the metal-poor stars are consistent with a single old stellar population, stars with abundances higher than [Fe/H] −1.3 dex are younger. The total age spread in ω Cent is about 3 Gyr. The monotonically increasing age-metallicity relation seems to level off above [Fe/H] −1.0 dex. Whether the star formation in ω Cen occured continuously or rather episodically has to be shown by combining more accurate abundances with highest quality photometry.
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://www.aanda.org/articles/aa/pdf/2004/28/aagd291.pdf
Alternate Webpage(s)	http://arxiv.org/pdf/astro-ph/0406017v1.pdf
Language	English
Access Restriction	Open
Subject Keyword	CEN/XFS Database Databases Dex Diagram Dietary Iron GUCY2C protein, human Photometry Sid Meier's Alpha Centauri Stars, Celestial Stellar (payment network) Virtual Link Trunking cyclophosphamide/etoposide/mitoxantrone
Content Type	Text
Resource Type	Article