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SBS 0335-052W: The Lowest-Metallicity Star-Forming Galaxy Known

Y. I. Izotov·T. X. Thuan·N. G. Guseva
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Abstract

We present 4-meter Kitt Peak telescope and 6.5-meter MMT spectrophotometry of the extremely low-metallicity galaxy SBS 0335-052W, the western companion of the blue compact dwarf galaxy SBS 0335-052E. These observations have been combined with published 10-meter Keck data to derive for the brightest region of SBS 0335-052W an oxygen abundance 12+logO/H=7.12+/-0.03. This makes SBS 0335-052W the lowest metallicity star-forming galaxy known in the local universe. Using a Monte Carlo technique, we fit the spectral energy distribution of SBS 0335-052W to derive the age of the oldest stars contributing to its optical light. We find that star formation in SBS 0335-052W began less than 500 Myr ago, making it a likely nearby young dwarf galaxy.

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Y. I. Izotov, T. X. Thuan, N. G. Guseva. 2005-06-21. SBS 0335-052W: The Lowest-Metallicity Star-Forming Galaxy Known. https://doi.org/10.1086/432874

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