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arXiv · 0707.2770

Neon Abundances from a Spitzer/IRS Survey of Wolf-Rayet Stars

R Ignace·J P Cassinelli·G Tracy·E B Churchwell·H J G L M Lamers
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Abstract

We report on neon abundances derived from {\it Spitzer} high resolution spectral data of eight Wolf-Rayet (WR) stars using the forbidden line of [\ion{Ne}{3}] 15.56 microns. Our targets include four WN stars of subtypes 4--7, and four WC stars of subtypes 4--7. We derive ion fraction abundances $γ$ of Ne^{2+} for the winds of each star. The ion fraction abundance is a product of the ionization fraction $Q_{\rm i}$ in stage i and the abundance by number ${\cal A}_E$ of element E relative to all nuclei. Values generally consistent with solar are obtained for the WN stars, and values in excess of solar are obtained for the WC stars.

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R Ignace, J P Cassinelli, G Tracy, E B Churchwell, H J G L M Lamers. 2007-07-18. Neon Abundances from a Spitzer/IRS Survey of Wolf-Rayet Stars. https://doi.org/10.1086/521718

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