Abundances on the Main Sequence of Omega Centauri

Abstract

Abundance ratios of carbon, nitrogen and strontium relative to iron, calculated using spectrum synthesis techniques, are given for a sample of main sequence and turnoff stars that belong to the globular cluster omega Centauri. The variations of carbon, nitrogen and/or strontium show several different abundance patterns as a function of [Fe/H]. The source of the enhancements/depletions in carbon, nitrogen and/or strontium may be enrichment from asymptotic giant branch stars of low (1--3 solar masses) and intermediate (3--8 solar masses) mass. Massive rotating stars which produce excess nitrogen without carbon and oxygen overabundances may also play a role. These abundances enable different contributors to be considered and incorporated into the evolutionary picture of omega Cen.

43 Pages, 13 Figures. Accepted for publication in ApJ

References in corpus (23)

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Cited by in corpus (22)

• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• Quantifying the Coexistence of Massive Black Holes and Dense Nuclear Star Clusters
• Chemical Enrichment in the Faintest Galaxies: the Carbon and Iron Abundance Spreads in the Boötes I Dwarf Spheroidal Galaxy and the Segue 1 System
• Sodium-oxygen anticorrelation and neutron capture elements in Omega Centauri stellar populations
• M 54 + Sagittarius = omega Centauri
• Fe and Al Abundances for 180 Red Giants in the Globular Cluster Omega Centauri (NGC 5139)
• Stromgren photometry of Galactic Globular Clusters. II Metallicity distribution of red giants in Omega Centauri
• Constraints on Helium Enhancement in the Globular Cluster M3 (NGC 5272): The Horizontal Branch Test
• A spectral atlas of post-main-sequence stars in omega Centauri: kinematics, evolution, enrichment and interstellar medium
• The double RGB in M 2: C, N, Sr and Ba abundances
• Nucleosynthesis in helium-enriched asymptotic giant branch models: Implications for Heavy Element Enrichment in Omega Centauri
• A Spectroscopic Survey for Omega Centauri Members at and beyond the Cluster Tidal Radius
• The impact of the 18F(a,p)21Ne reaction on asymptotic giant branch nucleosynthesis
• From the CMD of Omega Centauri and (super-)AGB stellar models to a Galactic plane passage gas purging chemical evolution scenario
• Abundances of C, N, Sr and Ba on the red giant branch of omega Centauri
• Confirming the intrinsic abundance spread in the globular cluster NGC 6273 (M 19) with calcium triplet spectroscopy
• Testing the AGB Scenario as the Origin of the Extreme-Helium Population in omega Centauri
• Possible Evidence for Metal Accretion onto the Surfaces of Metal-Poor Main-Sequence Stars
• Chemical evolution of star clusters
• Omega Centauri: weak MgH-band in red giants directly trace the helium content
• The quite complex "Simple Stellar Populations" of Globular Clusters
• A Main Sequence CH-star in the globular cluster M55 (NGC 6809)