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IR-source IRAS20508+2011: spectral variability of the central star

V. G. Klochkova·V. E. Panchuk·N. S. Tavolganskaya·G. Zhao·.
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Abstract

Over the five years of high-resolution spectroscopy of the cool star identified with the IR source IRAS20508+2011, the photospheric radial velocity variability Vr=15-30km/s is detected. In the same time, the Halpha profile varied from an intense bell-shaped emission line with a small absorption to 2-peaked emission with a central absorption feature below the continuum level. The NaD doublet lines shown a complex profile with broad (FWHM \approx 120km/s) emission and photospheric absorption, as well as an interstellar component. We used model atmospheres to determine the physical parameters and chemical composition of the star's atmosphere: Te=4800K, log g=1.5, [Fe/H]=-0.36, [O/Fe] =+1.79 (with the ratio [C/O]=-0.9). The totality of the parameters suggests that the optical component of IRAS20508+2011 is an O-rich AGB star with luminosity Mv

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V. G. Klochkova, V. E. Panchuk, N. S. Tavolganskaya, G. Zhao, .. 2006-05-06. IR-source IRAS20508+2011: spectral variability of the central star. https://doi.org/10.1134/s1063772906030073

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