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The Isotopic Mixture of Barium in the Metal-poor Subgiant HD 140283

David L. Lambert·Carlos Allende Prieto
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Abstract

Analyses of the abundances of neutron-capture elements have led to the belief that these elements in metal-poor stars are r-process products with relative abundances closely resembling those found in the solar system. This picture was challenged by Magain (1995), who found that a pure r-process mix of the barium isotopes was inconsistent with the mix of odd to even barium isotopes derived from analysis of the Ba II line at 4554 A in the spectrum of the metal-poor subgiant HD 140283. In this paper, we address Magain's challenge using new high resolution high signal-to-noise spectra of HD 140283, and find, in contrast to his result, that a solar-like r-process isotopic mixture provides a fair fit to the observed 4554 A profile.

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David L. Lambert, Carlos Allende Prieto. 2002-05-22. The Isotopic Mixture of Barium in the Metal-poor Subgiant HD 140283. https://doi.org/10.1046/j.1365-8711.2002.05643.x

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