Beryllium abundances in metal - poor stars ⋆
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چکیده
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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تاریخ انتشار 2008