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A Morphological Diagnostic for Dynamical Evolution of Wolf-Rayet Bubbles

Robert A. Gruendl·You-Hua Chu·Bryan C. Dunne·Sean D. Points
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Abstract

We have observed H-alpha and [OIII] emission from eight of the most well defined Wolf-Rayet ring nebulae in the Galaxy. We find that in many cases the outermost edge of the [OIII] emission leads the H-alpha emission. We suggest that these offsets, when present, are due to the shock from the Wolf-Rayet bubble expanding into the circumstellar envelope. Thus, the details of the WR bubble morphology at H-alpha and [OIII] can then be used to better understand the physical condition and evolutionary stage of the nebulae around Wolf-Rayet stars, as well as place constraints on the nature of the stellar progenitor and its mass loss history.

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Robert A. Gruendl, You-Hua Chu, Bryan C. Dunne, Sean D. Points. 2000-07-26. A Morphological Diagnostic for Dynamical Evolution of Wolf-Rayet Bubbles. https://doi.org/10.1086/316830

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