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arXiv · 2106.03781

The episodic dust-making Wolf-Rayet star HD 38030 in the Large Magellanic Cloud

Peredur M. Williams·Nidia I. Morrell·Konstantina Boutsia·Philip Massey
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Abstract

Mid-infrared photometry of the Wolf-Rayet star HD 38030 in the Large Magellanic Cloud from the NEOWISE-R mission show it to have undergone a dust-formation episode in 2018 and the dust to have cooled in 2019-20. New spectroscopy with the MagE spectrograph on the Magellan I Baade Telescope in 2019 and 2020 show absorption lines attributable to a companion of type near O9.7III-IV. We found a significant shift in the radial velocity of the C IV 5801-12 blend compared with the RVs measured in 1984 and 1993. The results combine to suggest that HD 38030 is a colliding-wind binary having short-lived dust formation episodes, like the Galactic systems WR 140 and WR 19, but at intervals in excess of 20 yr.

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Peredur M. Williams, Nidia I. Morrell, Konstantina Boutsia, Philip Massey. 2021-06-07. The episodic dust-making Wolf-Rayet star HD 38030 in the Large Magellanic Cloud. https://doi.org/10.1093/mnras%2Fstab1625

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