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arXiv · 0708.0096

Abundances on the Main Sequence of Omega Centauri

Laura M. Stanford·G. S. Da Costa·John E. Norris
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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.

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Laura M. Stanford, G. S. Da Costa, John E. Norris. 2007-08-01. Abundances on the Main Sequence of Omega Centauri. https://doi.org/10.1086/520794

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