Line Strengths in WN Stars
نویسندگان
چکیده
منابع مشابه
WN stars in the LMC: Parameters and atmospheric abundances
The spectra of 18 WN stars in the Large Magellanic Cloud (LMC) are quantitatively analyzed by means of “standard” Wolf-Rayet model atmospheres, using the helium and nitrogen lines as well as the spectral energy distribution. The hydrogen abundance is also determined. Carbon is included for a subset of 4 stars. The studied sample covers all spectral subtypes (WN2... WN9) and also includes one WN...
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We report the detection of WC stars in five WolfRayet (W-R) galaxies: He 2-10, NGC 3049, NGC 3125, NGC 5253 and Tol 89. The faint broad C IV λ5808 line requires sufficiently high S/N (>∼ 40) to be detected explaining the nondetection of this WC feature in previous observations. From the measurement of W-R emission lines (N III λ4640+C III λ4650, He II λ4686, and C IV λ5808), we conclude that al...
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We consider the relationships between the classification parameters of WN stars in the new 3-dimensional classification of Smith et al. (1996) and the corresponding and related parameters that define stellar atmosphere models. Specifically, we consider: FWHM of HeII 4686 vs. v∞; hydrogen content by direct inspection vs. hydrogen content by modelling and vs. colour (b-v)0; ionisation subclass an...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1982
ISSN: 0074-1809
DOI: 10.1017/s0074180900028655