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arXiv · 2507.17946

The Ejecta Nebula Around the Wolf-Rayet Star WR 71

Robert A. Fesen·Manuel C. Peitsch·Martin R. Pugh·Bray Falls·Marcel Drechsler
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Abstract

We present deep H$α$ and [O III] images of the ejecta rich nebulosity associated with the suspected runaway and binary Wolf-Rayet star WR~71 (HD 143414). In H$α$ emission, the nebula appears as a crescent shaped, broken ring of clumpy emission some $9' \times 13'$ in angular size centered to the south and west of the WR star. At a Gaia estimated distance of 4.27 kpc, the nebula has physical dimensions of $11 \times 16$ pc making it one of the larger known ejecta rich WR ring nebulae. Our [O III] image also show considerable surrounding faint nebulosity much of which may be unrelated to the WR star. A comparison of the nebula's optical appearance with that seen in WISE 22 $μ$m data shows infrared coincidence with the nebula's brightest [O III] emission features. Deep H$α$ and [O III] images like those presented here suggests that new and substantially deeper imaging reconnaissance of WR star nebulae compared to earlier surveys may lead to additional WR ring nebula detections, thereby enhancing our understanding on the frequency and formation of WR ring nebulae.

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Robert A. Fesen, Manuel C. Peitsch, Martin R. Pugh, Bray Falls, Marcel Drechsler. 2025-07-23. The Ejecta Nebula Around the Wolf-Rayet Star WR 71. https://arxiv.org/abs/2507.17946

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