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The neon abundance in WC stars. II. ISO-SWS spectroscopy of WR 90 (HD 156385)

Published online by Cambridge University Press:  25 May 2016

Luc Dessart
Affiliation:
Department of Physics & Astronomy, UCL, Gower St., London, WC1E 6BT, UK
Allan J. Willis
Affiliation:
Department of Physics & Astronomy, UCL, Gower St., London, WC1E 6BT, UK
Paul A. Crowther
Affiliation:
Department of Physics & Astronomy, UCL, Gower St., London, WC1E 6BT, UK
Patrick W. Morris
Affiliation:
SRON, Sorbonnelaan 2, NL-3584 CA, Utrecht, the Netherlands
D. John Hillier
Affiliation:
Department of Physics & Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA

Abstract

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In general, observationally derived wind compositions of WR stars are in reasonable agreement with predictions from stellar evolution models for massive stars. However, Barlow et al. (1988) identified a major discrepancy for neon in γ2 Vel (WC8+O) using ground-based observations. The advent of the ESA Infrared Space Observatory (ISO) has allowed the study of neon in many more WC stars, using mid-IR fine structure lines ([Ne II] 12.81 μm, [NeIII] 15.55μm and [NEV] 14.32 μm). Willis et al. (1998) used ISO-SWS observations of WR 146 (WC5+O) to derive a neon abundance that was within the range expected theoretically. Here we undertake a study of WR 90 (HD 156385), the only (apparently) single WC7 star in our Galaxy, using ISO-SWS spectroscopy. The only spectroscopic neon feature in the mid-IR of WR 90 is [Ne III] 15.55 μm, in addition to numerous C IV and He II transitions (see Figure 1).

Type
Part 2. Models for single star evolution of massive stars: wind + atmosphere + interior
Copyright
Copyright © Astronomical Society of the Pacific 1999 

References

Barlow, M.J., Roche, P., Aitken, D.A. 1988, MNRAS 232, 821 Google Scholar
Hillier, D.J. 1989, ApJ 347, 392 Google Scholar
Hillier, D.J. 1990, ApJ 231, 116 Google Scholar
Hillier, D.J., Miller, D.L. 1998, ApJ 496, 407 CrossRefGoogle Scholar
Willis, A.J., Dessart, L., Crowther, P.A., Morris, P.W., Maeder, A., Conti, P.S., van der Hucht, K.A. 1988, MNRAS 290, 371 CrossRefGoogle Scholar