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Many works engaged to investigate the astrophysical origin of the neutron capture elements in the metal-poor star HD 140283.However,no definite conclusions have been drawn.In this work,using the abund
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Many works engaged to investigate the astrophysical origin of the neutron capture elements in the metal-poor star HD 140283.However,no definite conclusions have been drawn.In this work,using the abundance-decomposed 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 originate 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 robust nature.On the other hand,we find that abundance robust nature 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 be used to investigate the astrophysical origins of the elements in the metal-poor stars and population I stars.
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