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Chemical Abundance Variations in Globular Clusters: Recent Results from Mildly Metal-Poor M5

Inese I. Ivans·Robert P. Kraft·Chris Sneden·Graeme H. Smith·R. Michael Rich·Matthew Shetrone
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Abstract

We present a chemical composition analysis of 36 giant stars in mildly metal-poor globular cluster M5. In comparing the M5 results to those obtained in M4, a cluster previously considered to be a ``twin'' in age, metallicity and chemical composition, we find large star-to-star variations in the abundances of elements sensitive to proton-capture nucleosynthesis, similar [Fe/H] values, but factor of two differences in some alpha-capture, odd-Z and slow neutron-capture process elements. Among stars in globular clusters, apparently there are no definitive ``single'' values of [el/Fe] at a given [Fe/H] for many important elements.

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Inese I. Ivans, Robert P. Kraft, Chris Sneden, Graeme H. Smith, R. Michael Rich, Matthew Shetrone. 2001-09-12. Chemical Abundance Variations in Globular Clusters: Recent Results from Mildly Metal-Poor M5. https://arxiv.org/abs/astro-ph/0109195

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