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SBS 0335-052W - an Extremely Low Metallicity Dwarf Galaxy

V. A. Lipovetsky·F. H. Chaffee·Y. I. Izotov·C. B. Foltz·A. Y. Kniazev·U. Hopp
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Abstract

We present Multiple Mirror Telescope (MMT) and Keck II telescope spectrophotometry and 3.5m Calar Alto telescope R, I photometry of the western component of the extremely low-metallicity blue compact galaxy SBS 0335-052. The components, separated by 22 kpc, appear to be members of a unique, physically connected system. It is shown that SBS 0335-052W consists of at least three stellar clusters and has the same redshift as SBS 0335-052. The oxygen abundance in its two brightest knots is extremely low, 12+log(O/H)= 7.22+/-0.03 and 7.13+/-0.08, respectively. These values are lower than in SBS 0335-052 and are nearly the same as those in I Zw 18. The (R-I) color profiles are very blue in both galaxies due to the combined effects of ionized gas and a young stellar population emission. We argue that SBS 0335-052W is likely to be a nearby, young dwarf galaxy.

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V. A. Lipovetsky, F. H. Chaffee, Y. I. Izotov, C. B. Foltz, A. Y. Kniazev, U. Hopp. 1999-02-25. SBS 0335-052W - an Extremely Low Metallicity Dwarf Galaxy. https://doi.org/10.1086/307335

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