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arXiv · 2505.13269

Correlation between U/Th and Pb/Os abundance ratios and its application in nuclear cosmochronology

Y. Y. Huang·Q. Q. Cui·X. H. Wu·S. Q. Zhang
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Abstract

The abundance ratios of radioactive elements U/Th and stable elements Pb/Os from the $r$-process are found to have a strong correlation. This correlation is quite robust with respect to astrophysical conditions. The U/Th-Pb/Os correlation is then applied to provide customized initial abundance ratios U/Th from the observed abundance ratios Pb/Os for six $r$-process enhanced metal-poor stars respectively. Ages of these six metal-poor stars are predicted by the U/Th chronometer, which are approximately between $11$ and $15$ Gyr. Their ages are compatible with the cosmic age of 13.8 billion years predicted from the cosmic microwave background radiation.

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Y. Y. Huang, Q. Q. Cui, X. H. Wu, S. Q. Zhang. 2025-05-19. Correlation between U/Th and Pb/Os abundance ratios and its application in nuclear cosmochronology. https://doi.org/10.3847/1538-4357%2Fade390

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