Deep FORS1 Observations of the Double Main Sequence of ω Centauri

2006/09/25 by A. Sollima, F. R. Ferraro, M. Bellazzini +3 · 5 citations
Chemistry · Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Chemistry #Cluster (spacecraft) #Computer science #Main sequence #Physics #Sequence (biology) #Stars #Stellar, planetary, and galactic studies #astro-ph

paper · pdf · doi:10.1086/509711

published as Astrophys.J.654:915-922,2007 · 15 pages, 10 figures, accepted for publication by ApJ

arxiv created 2006/09/25 · openalex publication_date 2007/01/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We present the results of a deep photometric survey performed with the VLT FORS1 aimed at investigating the complex main-sequence structure of the stellar system ω Centauri. We confirm the presence of a double main sequence and identify its blue component (bMS) over a large field of view up to 26' from the cluster center. We found that bMS stars are significantly more concentrated toward the cluster center than the other "normal" MS stars. The bMS morphology and its position in the CMD have been used to constrain the helium overabundance required to explain the observed MS morphology.

Citations

• The initial helium abundance of the Galactic globular cluster system
• A multidimensional version of the Kolmogorov–Smirnov test
• The Origin of the Double Main Sequence in ω Centauri: Helium Enrichment due to Gas Fueling from Its Ancient Host Galaxy?
• Metallicities on the Double Main Sequence of ω Centauri Imply Large Helium Enhancement
• Solar System Abundances and Condensation Temperatures of the Elements
• The Discovery of an Anomalous Subgiant Branch in the Color-Magnitude Diagram of Centauri
• Two-dimensional goodness-of-fit testing in astronomy

Cited by

• THE RR LYRAE VARIABLES AND HORIZONTAL BRANCH OF NGC 6656 (M22),
• FROM THE COLOR-MAGNITUDE DIAGRAM OF ω CENTAURI AND (SUPER-)ASYMPTOTIC GIANT BRANCH STELLAR MODELS TO A GALACTIC PLANE PASSAGE GAS PURGING CHEMICAL EVOLUTION SCENARIO
• STRUCTURAL PROPERTIES OF ULTRA-COMPACT DWARF GALAXIES IN THE FORNAX AND VIRGO CLUSTERS
• Observing multiple stellar populations with VLT/FORS2: Main sequence photometry in outer regions of NGC 6752, NGC 6397, and NGC 6121 (M 4)
• Dynamical evolution of multiple-population globular clusters