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Chemical Properties of Star-Forming Emission Line Galaxies at z=0.1 - 0.5

Henry A. Kobulnicky·Dennis Zaritsky
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Abstract

We measure oxygen and nitrogen abundances for 14 star-forming emission line galaxies (ELGs) at 0.11 -1.4 like local spirals. These chemical properties are inconsistent with unevolved objects undergoing a first burst of star formation. The majority of the ELGs are presently ~4 magnitudes brighter and ~0.5 dex more metal-rich than the bulk of the stars in well-known metal-poor dwarf spheroidals such as NGC 205 and NGC 185, making an evolution between some ELGs and metal-poor dwarf spheroidals improbable. However, the data are consistent with the hypothesis that more luminous and metal-rich spheroidal galaxies like NGC 3605 may become the evolutionary endpoints of some ELGs. [abridged]

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Henry A. Kobulnicky, Dennis Zaritsky. 1998-08-09. Chemical Properties of Star-Forming Emission Line Galaxies at z=0.1 - 0.5. https://doi.org/10.1086/306673

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