Bright Stars and Metallicity Spread in the Globular Cluster Omega Centauri

Sergio Ortolani; Stefano Covino; Giovanni Carraro

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Bright Stars and Metallicity Spread in the Globular Cluster Omega Centauri

Sergio Ortolani·Stefano Covino·Giovanni Carraro

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Abstract

The globular cluster Omega Centauri (NGC 5139) is the most massive and brightest cluster in our Galaxy. It has also a moderately high mass to light ratio (3.6) and an anomalous flattening (0.83) for a globular cluster. This cluster is also very interesting because it is one of a few examples of globular clusters with a measurable spread in the metal abundance (see Da Costa & Willumsen 1981, Norris et al. 1996, and Suntzeff and Kraft 1996 and references therein) and then it offers a unique, big sample of nearby stars having all the same distance and reddening but showing different metallicity (and age ?) effects. A recent paper by Norris et al. (1997) shows also an interesting correlation between kinematics and metal abundance.

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Sergio Ortolani, Stefano Covino, Giovanni Carraro. 1998-10-20. Bright Stars and Metallicity Spread in the Globular Cluster Omega Centauri. https://arxiv.org/abs/astro-ph/9810310

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