We present results of an extensive spectroscopic survey of subgiant stars in the stellar system omega Cen. Using infrared Ca II triplet lines, we derived metallicities and radial velocities for more than 250 stars belonging to different stellar populations of the system. We find that the most metal-rich component, the anomalous subgiant branch (SGB-a), has a metallicity of [Fe/H]~-0.6, fully compatible with that determined along the anomalous red giant branch (RGB-a). Our analysis suggests that the age of this component and of the other metal-intermediate (-1.4
Metallicities, Relative Ages, and Kinematics of Stellar Populations in omega Centauri / Sollima A.; Pancino E.; Ferraro F. R.; Bellazzini M.; Straniero O.; Pasquini L.. - In: THE ASTROPHYSICAL JOURNAL. - ISSN 0004-637X. - STAMPA. - 634:(2005), pp. 332-343. [10.1086/496945]
Metallicities, Relative Ages, and Kinematics of Stellar Populations in omega Centauri
SOLLIMA, ANTONIO;FERRARO, FRANCESCO ROSARIO;
2005
Abstract
We present results of an extensive spectroscopic survey of subgiant stars in the stellar system omega Cen. Using infrared Ca II triplet lines, we derived metallicities and radial velocities for more than 250 stars belonging to different stellar populations of the system. We find that the most metal-rich component, the anomalous subgiant branch (SGB-a), has a metallicity of [Fe/H]~-0.6, fully compatible with that determined along the anomalous red giant branch (RGB-a). Our analysis suggests that the age of this component and of the other metal-intermediate (-1.4I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
