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Detection of low Eu abundances in extremely metal-poor stars and the origin of r-process elements

Yuhri Ishimaru·Shinya Wanajo·Wako Aoki·Sean G. Ryan
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Abstract

We report abundance analyses of three extremely metal-poor stars with [Fe/H] $\lesssim -3$, using the Subaru High Dispersion Spectrograph (HDS). All are found to have sub-solar values of [Eu/Fe]. Comparison with our chemical evolution model of the Galactic halo implies the dominant source of Eu to be the low-mass end of the supernova mass range. Future studies of stars with low Eu abundances will be important to determine the r-process site.

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Yuhri Ishimaru, Shinya Wanajo, Wako Aoki, Sean G. Ryan. 2003-11-06. Detection of low Eu abundances in extremely metal-poor stars and the origin of r-process elements. https://doi.org/10.1086/381496

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