New Rare Earth Element Abundance Distributions for the Sun and Five r-Process-Rich Very Metal-Poor Stars

TL;DR

This study derives new rare-earth element abundances for the Sun and five metal-poor stars, enabling a detailed comparison of stellar and solar r-process element distributions.

Contribution

It provides the first consistent abundance measurements of several rare-earth elements in both the Sun and metal-poor stars, improving understanding of r-process nucleosynthesis.

Findings

Solar and meteoritic abundances agree for all five elements.

Consistent r-process element distributions were established for the stars.

Comparison reveals similarities and differences between stellar and solar r-process patterns.

Abstract

We have derived new abundances of the rare-earth elements Pr, Dy, Tm, Yb, and Lu for the solar photosphere and for five very metal-poor, neutron-capture r-process-rich giant stars. The photospheric values for all five elements are in good agreement with meteoritic abundances. For the low metallicity sample, these abundances have been combined with new Ce abundances from a companion paper, and reconsideration of a few other elements in individual stars, to produce internally-consistent Ba, rare-earth, and Hf (56<= Z <= 72) element distributions. These have been used in a critical comparison between stellar and solar r-process abundance mixes.