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arXiv · 1303.2603

Individual Alpha Elements, C, N, and Ba in Early Type Galaxies

Guy Worthey·Baitian Tang·Jedidiah Serven
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Abstract

Spectral data on early type galaxies is analyzed for chemical abundance with an emphasis on obtaining detailed abundances for the elements O and Si in addition to C, N, Na, Mg, Ca, Fe, and Ba. The abundance trends with velocity dispersion fit preconceptions based upon previous Mg conclusions, namely that larger galaxies have a higher alpha element to iron peak ratio indicative of a higher ratio of Type II to Type Ia supernova products. The heaviest alpha elements, Ca and Ti, do not participate in this trend, although this fact does not necessarily alter the basic picture given the uncertainties in nucleosynthetic yields. Elements that likely have significant contributions from intermediate-mass stars, namely C, N, and Ba, also gain ground relative to Fe in massive galaxies at a modest level, with the Ba conclusion uncertain from our data alone.

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Guy Worthey, Baitian Tang, Jedidiah Serven. 2013-03-11. Individual Alpha Elements, C, N, and Ba in Early Type Galaxies. https://doi.org/10.1088/0004-637x/783/1/20

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