Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-09-05
Astrophys.J.634:332-343,2005
Astronomy and Astrophysics
Astrophysics
33 pages, 12 figures, accepted by ApJ
Scientific paper
10.1086/496945
We present results of an extensive spectroscopic survey of Subgiant stars in the stellar system omega Centauri. Using infrared CaII 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 Sub Giant 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 < [Fe/H] < -1.0) stellar populations of the system are all comparable to that of the dominant metal poor population within 2 Gyr regardless of any choice of helium abundance. These results impose severe constraints on the time-scale of the enrichment process of this stellar system, excluding the possibility of an extended star formation period. The radial velocity analysis of the entire sample demonstrates that only the metal-intermediate populations are kinematically cooler than the others.
Bellazzini Michele
Ferraro Francesco R.
Pancino Elena
Pasquini Luca
Sollima Antonio
No associations
LandOfFree
Metallicities, relative ages and kinematics of stellar populations in omega Centauri does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Metallicities, relative ages and kinematics of stellar populations in omega Centauri, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Metallicities, relative ages and kinematics of stellar populations in omega Centauri will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-378720