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

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 $\gamma$ of Ne^{2+} for the winds of each star. The ion fraction abundance is a product of the ionization fraction $Q_{\mathrm{i}}$ in stage i and the abundance by number ${\mathcal{A}}_E$ 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.

arXiv commentto appear in Astrophysical Journal

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• Investigation of [KSF2015] 1381-19L, a WC9-type star in the high extinction Galactic region
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