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Europium Isotopic Abundances in Very Metal-poor Stars

Christopher Sneden·John J. Cowan·James E. Lawler·Scott Burles·Timothy C. Beers·George M. Fuller
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Abstract

Europium isotopic abundance fractions are reported for the very metal-poor, neutron-capture-rich giant stars CS 22892-052, HD 115444, and BD +17 3248. The abundance fractions, derived from analysis of several strong Eu II lines appearing in high-resolution spectra of these stars, are in excellent agreement with each other and with their values in the Solar System: fraction(\iso{Eu}{151}) ~= fraction(\iso{Eu}{153}) ~= 0.5. Detailed abundance studies of very metal-poor stars have previously shown that the total elemental abundances of stable atoms with atomic numbers z >= 56 typically match very closely those of a scaled solar-system r-process abundance distribution. The present results for the first time extend this agreement to the isotopic level.

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Christopher Sneden, John J. Cowan, James E. Lawler, Scott Burles, Timothy C. Beers, George M. Fuller. 2002-01-28. Europium Isotopic Abundances in Very Metal-poor Stars. https://doi.org/10.1086/339471

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