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arXiv · 0707.2881

VLT spectroscopy of blue supergiants in IC 1613

Fabio Bresolin·Miguel A. Urbaneja·Wolfgang Gieren·Grzegorz Pietrzynski·Rolf-Peter Kudritzki
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Abstract

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 B- and 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 HII regions in which we detect the temperature-sensitive [OIII]4363 auroral line.

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Fabio Bresolin, Miguel A. Urbaneja, Wolfgang Gieren, Grzegorz Pietrzynski, Rolf-Peter Kudritzki. 2007-07-19. VLT spectroscopy of blue supergiants in IC 1613. https://doi.org/10.1086/522571

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