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arXiv · 1511.01832

Probing Wolf-Rayet Winds: Chandra/HETG X-Ray Spectra of WR 6

David P. Huenemoerder·Kenneth G. Gayley·Wolf-Rainer Hamann·Richard Ignace·Joy S. Nichols·Lidia Oskinova·Andrew M. T. Pollock·Norbert S. Schulz·Tomer Shenar
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Abstract

With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding spherical wind of high X-ray-continuum optical depth. The presence of strong helium-like forbidden lines places the source of X-ray emission at tens to hundreds of stellar radii from the photosphere. Variability was present in X-rays and simultaneous optical photometry, but neither were correlated with the known period of the system or with each other. An enhanced abundance of sodium revealed nuclear processed material, a quantity related to the evolutionary state of the star. The characterization of the extent and nature of the hot plasma in WR 6 will help to pave the way to a more fundamental theoretical understanding of the winds and evolution of massive stars.

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David P. Huenemoerder, Kenneth G. Gayley, Wolf-Rainer Hamann, Richard Ignace, Joy S. Nichols, Lidia Oskinova, Andrew M. T. Pollock, Norbert S. Schulz, Tomer Shenar. 2015-11-05. Probing Wolf-Rayet Winds: Chandra/HETG X-Ray Spectra of WR 6. https://doi.org/10.1088/0004-637x%2F815%2F1%2F29

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