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Detection of elements beyond the Ba-peak in VLT+UVES spectra of post-AGB stars

Maarten Reyniers·Hans Van Winckel
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Abstract

In this letter, we report on our successful systematic search for lines of elements beyond the Ba-peak in spectra of s-process enriched post-AGB stars. Using newly released atomic data from both the VALD database and the D.R.E.A.M. project, we could derive abundances for several elements heavier than europium for three objects, on the base of high quality VLT+UVES spectra. The abundances of these elements are of particular interest since they turn out to be powerful constraints for chemical evolutionary AGB models. Their high abundances indicate that, also in only moderately metal deficient AGB stars, production of lead is expected to be significant.

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Maarten Reyniers, Hans Van Winckel. 2003-08-04. Detection of elements beyond the Ba-peak in VLT+UVES spectra of post-AGB stars. https://doi.org/10.1051/0004-6361%3A20031200

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