VLT spectroscopy of blue supergiants in IC 1613

TL;DR

This study provides a detailed spectral catalog and chemical abundance measurements of 54 massive stars in IC 1613, revealing insights into the galaxy's stellar populations and metallicity.

Contribution

It offers the first comprehensive spectral classification and chemical analysis of massive stars in IC 1613, including the discovery of Be stars beyond the Magellanic Clouds.

Findings

Mean oxygen abundance of 12+log(O/H)=7.90 +/- 0.08.

Detection of 6 Be stars beyond the Magellanic Clouds.

Spectral classification of 54 OBA stars in IC 1613.

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.