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arXiv · 1511.04666

Study of the element abundances in HD 140283: the abundance robustness of the weak r- and main r-process stars

Ping Niu·Wenyuan Cui·Bo Zhang
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Abstract

Many works have attempted to investigate the astrophysical origin of the neutron-capture elements in the metalpoor star HD 140283. However, no definite conclusions have been drawn. In this work, using the abundancedecomposed approach, we find that the metal-poor star HD 140283 is a weak r-process star. Although this star is a weak r-process star, its Ba abundance mainly originates from the main r-process. This is the reason that the ratio [Ba/Eu]= -0.58+- 0.15 for HD 140283 is close to the ratio of the main r-process. Based on the comparison of the abundances in the six-weak r-process stars, we find that their element abundances possess a robust nature. On the other hand, we find that the robust nature of the abundance of the extreme main r-process stars ([r/Fe]>= 1.5) can be extended to the lighter neutron-capture elements. Furthermore, the abundance characteristics of the weak r-process and main r-process are investigated. The abundance robustness of the two category r-process stars could be used as the constraint of the r-process theory and could be used to investigate the astrophysical origins of the elements in the metal-poor stars and population I stars.

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Ping Niu, Wenyuan Cui, Bo Zhang. 2015-11-15. Study of the element abundances in HD 140283: the abundance robustness of the weak r- and main r-process stars. https://doi.org/10.1088/0004-637x%2F813%2F1%2F56

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