Journal ArticleDOI
MG and Fe absorption features in elliptical galaxies
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In this paper, Fe and Mg indices from two homogenous collections of nuclear elliptical galaxy spectra are compared with model indices. And the average giant elliptical, the [Mg/Fe] ratio exceeds that of the most metal-rich stars in the solar neighborhood by ∼ 0.2-0.3 dex.Abstract:
Fe and Mg indices from two homogenous collections of nuclear elliptical galaxy spectra are compared with model indices. In the average giant elliptical, the [Mg/Fe] ratio exceeds that of the most metal-rich stars in the solar neighborhood by ∼0.2-0.3 dex, with a large spread about this mean. This result implies a variable «enrichment effectiveness» of Type II supernovae (SNs) compared with Type Ia SNs in the evolution of ellipticals, caused perhaps by differences in star formation time scales, the initial mass function, or the amount of Fe versus Mg ejected in galactic windsread more
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