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arXiv · 2209.06043

Investigating the impact of different velocity fields on the spectral appearance of Wolf-Rayet stars

Roel R. Lefever·Tomer Shenar·Andreas A. C. Sander·Luka Poniatowski·Karan Dsilva·Helge Todt
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Abstract

The emission line spectra of WR stars are often formed completely in the optically thick stellar wind. Hence, any assumption on the wind velocity law in a spectral analysis has a profound impact on the determination of the stellar parameters. By comparing Potsdam Wolf-Rayet (PoWR) model spectra calculated with different $β$ laws, we show that the velocity field heavily influences the spectra: by using the appropriate $β$ laws, the entire range of late and early types can be covered with the same stellar model.

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Roel R. Lefever, Tomer Shenar, Andreas A. C. Sander, Luka Poniatowski, Karan Dsilva, Helge Todt. 2022-09-13. Investigating the impact of different velocity fields on the spectral appearance of Wolf-Rayet stars. https://doi.org/10.1017/s1743921322002083

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