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arXiv · 1708.05686

Carbon-enhanced metal-poor 3D model atmospheres

M. Steffen·A. J. Gallagher·E. Caffau·P. Bonifacio·H. -G. Ludwig
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Abstract

We present our latest 3D model atmospheres for carbon-enhanced metal-poor (CEMP) stars computed with the CO5BOLD code. The stellar parameters are representative of hot turn-off objects (Teff ~ 6250 K, log g=4.0, [Fe/H]=-3.0). The main purpose of these models is to investigate the role of 3D effects on synthetic spectra of the CH G-band (4140-4400 A), the CN BX-band (3870-3890 A), and several UV OH transitions (3122-3128 A). By comparison with the synthetic spectra from standard 1D model atmospheres (assuming local thermodynamic equilibrium, LTE), we derive 3D abundance corrections for carbon and oxygen of up to -0.5 and -0.7 dex, respectively.

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M. Steffen, A. J. Gallagher, E. Caffau, P. Bonifacio, H. -G. Ludwig. 2017-08-17. Carbon-enhanced metal-poor 3D model atmospheres. https://doi.org/10.1017/s1743921317007062

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