The Ejecta Nebula Around the Wolf-Rayet Star WR 71

TL;DR

This paper presents deep optical imaging of the large, ejecta-rich nebula around Wolf-Rayet star WR 71, revealing its structure and infrared correlation, and suggests that deeper imaging could uncover more such nebulae.

Contribution

It provides detailed optical images of WR 71's nebula, demonstrating the potential for deeper surveys to discover more WR ring nebulae and improve understanding of their formation.

Findings

Nebula is a large, crescent-shaped structure around WR 71.

Infrared data coincides with brightest optical emission regions.

Deeper imaging may reveal more WR nebulae.

Abstract

We present deep H$\alpha$ 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$\alpha$ 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 $\mu$m data shows infrared coincidence with the nebula's brightest [O III] emission features. Deep H$\alpha$ 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.