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Abundance Ratios in Early-Type Galaxies

Reynier Peletier
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Abstract

Although evidence is accumulating that abundance ratios in galaxies are often non-solar, they are far from understood. I resume the current evidence for non-solar abundance ratios, supplementing the recent review by Worthey (1998) with some new results. It appears that the Mg/Fe abundance ratio only depends on the mass of the galaxy, not on the formation time-scale. For massive galaxies [Mg/Fe] > 0, while small galaxies show solar abundance ratios. Information about abundances of other element is scarce, but new evidence is given that [Ca/Fe] is solar, or slightly lower than solar, contrary to what is expected for an alpha-element.

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Reynier Peletier. 1999-04-21. Abundance Ratios in Early-Type Galaxies. https://arxiv.org/abs/astro-ph/9904280

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