Vlt Spectroscopy of Blue Supergiants in Ic 1613 1
نویسنده
چکیده
We present multi-object spectroscopy of young, massive stars in the Local Group galaxy IC 1613. We provide the spectral classification and a detailed spectral catalog for 54 OBA stars in this galaxy. The majority of the photometrically selected sample is composed of Band A-type supergiants. The remaining stars include early O-type dwarfs and the only Wolf-Rayet star known in this galaxy. Among the early B stars we have serendipitously uncovered 6 Be stars, the largest spectroscopically confirmed sample of this class of objects beyond the Magellanic Clouds. We measure chemical abundances for 9 early-B supergiants, and find a mean oxygen abundance of 12 + log(O/H) = 7.90 ± 0.08. This value is consistent with the result we obtain for two H II regions in which we detect the temperature-sensitive [O III]λ 4363 auroral line. Subject headings: galaxies: abundances — galaxies: stellar content — galaxies: individual (IC 1613) — stars: early-type
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