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arXiv · 0810.2600

Beryllium abundances in metal-poor stars

K. F. Tan·J. R. Shi·G. Zhao
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Abstract

We have determined beryllium abundances for 25 metal-poor stars based on the high resolution and high signal-to-noise ratio spectra from the VLT/UVES database. Our results confirm that Be abundances increase with Fe, supporting the global enrichment of Be in the Galaxy. Oxygen abundances based on [O I] forbidden line implies a linear relation with a slope close to one for the Be vs. O trend, which indicates that Be is probably produced in a primary process. Some strong evidences are found for the intrinsic dispersion of Be abundances at a given metallicity. The deviation of HD132475 and HD126681 from the general Be vs. Fe and Be vs. O trend favours the predictions of the superbubble model, though the possibility that such dispersion originates from the inhomogeneous enrichment in Fe and O of the protogalactic gas cannot be excluded.

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K. F. Tan, J. R. Shi, G. Zhao. 2008-10-15. Beryllium abundances in metal-poor stars. https://doi.org/10.1111/j.1365-2966.2008.14027.x

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