河北师范大学学报—

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刊名：河北师范大学学报（自然科学版）Journal of Hebei Normal University (Natural Science)
主办：河北师范大学
ISSN： 1000-5854
CN： 13-1061/N
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贫金属星2MASS J00512646-1053170 元素核合成机制

韩万强¹

杨国超²

李志坤³

(1.石家庄学院理学院,石家庄 050035; 2.西华师范大学物理与天文学院,南充 637002; 3.河北省科学技术馆,石家庄 050035)
DOI： 10.13763/j.cnki.jhebnu.nse.202502006

Study on Nucleosynthesis Scenario of Elements in Metal-poor Star 2MASS J00512646-1053170

HAN Wanqiang¹,YANG Guochao²,LI Zhikun³

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摘要/Abstract

摘要：

2MASS J00512646-1053170是一颗极贫金属星（[Fe/H]=-2.31），与太阳相比，该星的Ge和Eu元素显著增丰（[Ge/Fe]=0.1，[Eu/Fe]=1.37）.另外，元素Cd的丰度达到了[Cd/Fe]=1.27，显著高于目前已观测到的贫金属星.通过利用丰度分解的方法分析该星的元素丰度特征发现，该星的轻元素和铁族元素由大质量星的primary过程主导，重中子俘获元素（Z≥56）主要由主要r-过程合成，轻中子俘获元素（Sr，Y，Zr）主要由主要s-过程和主要r-过程产生.这2个核合成的贡献分别占总丰度的46%和41%，而弱r-过程贡献很小，仅为13%.Cd元素的高度增丰是由主要r-过程决定的，其丰度有88%来自于主要r-过程的贡献.Ge元素的丰度只有19.4%来自大质量星的secondary过程，另外的80.6%来自中子俘获过程，其中主要r-、弱r-、主要s-和弱s-过程的贡献分别占总丰度的10.8%，15.6%，33.2%，20.1%.

Abstract：

As a very metal-poor star([Fe/H]=-2.31),2MASS J00512646-1053170 is enhanced highly in the elemental abundances of Ge([Ge/Fe]=0.1)and Eu([Eu/Fe]=1.37),and the abundance of Cd is the highest among all the metal-poor stars([Cd/Fe]=1.27).Using the abundance decomposition method,we analyze and study the elemental abundance features and find that,the light elements and iron-group elements in the star mainly come from the primary process of the massive stars.The heavier neutron-capture elements(Z≥56)are produced dominantly from the main r-process.The lighter neutron-capture elements(Sr,Y,Zr)originate mainly from the main s-process(~46%)and main r-process(~41%),with a little fraction from the weak r-process(~13%).The highly enrichment of element Cd is dominated by the main r-process due to that about 88 percent of abundance contributions come from it.The element Ge in the star may come from multiple astrophysical processes.About 80.6 percent of Ge abundance are contributed by the neutron-capture process and the other 19.4 percent of that may come from the secondary process in massive stars.The contribution proportions of the main r-,weak r-,main s-,and weak s-process are 10.8%,15.6%,33.2%,and 20.1% respectively.

关键词

关键词： 贫金属星 ; 大质量星 ; r-过程 ; 丰度

Key words： metal-poor star ; massive star ; r-process ; abundance

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