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Accurate LTE abundances for some lambda Boo stars

S. M. Andrievsky·I. V. Chernyshova·V. G. Klochkova·V. E. Panchuk
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Abstract

High-resolution and high S/N CCD spectra were analyzed to determine accurate LTE abundances in four lambda Boo stars: pi^1 Ori, 29 Cyg, HR 8203 and 15 And. In general, 14 chemical elements were investigated. The main results are the following: all stars have a strong deficiency of the majority of investigated metals. Oxygen exhibits a moderate deficiency. The carbon abundance is close to the solar one. The results obtained support an accretion/diffusion model, which is currently adopted for the explanation of the lambda Boo phenomenon.

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S. M. Andrievsky, I. V. Chernyshova, V. G. Klochkova, V. E. Panchuk. 1998-05-18. Accurate LTE abundances for some lambda Boo stars. https://arxiv.org/abs/astro-ph/9805226

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