Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-02-28
Astrophys.J. 623 (2005) 860-865
Astronomy and Astrophysics
Astrophysics
Accepted for publication on ApJ. High resolution figures can be downloaded from ftp://ftp.mporzio.astro.it/dist/monelli2/
Scientific paper
10.1086/428643
We present three different optical and near-infrared (NIR) data sets for evolved stars in the Galactic Globular Cluster Omega Cen The comparison between observations and homogeneous sets of stellar isochrones and Zero-Age Horizontal Branches provides two reasonable fits. Both of them suggest that the so-called anomalous branch has a metal-intermediate chemical composition (-1.1 < [Fe/H] < -0.8) and is located ~500 pc beyond the bulk of Omega Cen stars. These findings are mainly supported by the shape of the subgiant branch in four different color-magnitude diagrams (CMDs). The most plausible fit requires a higher reddening, E(B-V)=0.155 vs. 0.12, and suggests that the anomalous branch is coeval, within empirical and theoretical uncertainties, to the bulk of Omega Cen stellar populations. This result is supported by the identification of a sample of faint horizontal branch stars that might be connected with the anomalous branch. Circumstantial empirical evidence seems to suggest that the stars in this branch form a clump of stars located beyond the cluster.
Andersen Michael I.
Bono Giuseppe
Buonanno Roberto
Calamida Annalisa
Corsi Carlo E.
No associations
LandOfFree
On the anomalous red giant branch of the globular cluster Omega Cen 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 On the anomalous red giant branch of the globular cluster Omega Cen, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the anomalous red giant branch of the globular cluster Omega Cen will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-142051