Pollution tracks of r-process material in [Sr/Ba] vs. [Ba/Fe] space for the early Galaxy
Pollution tracks of r-process material in [Sr/Ba] vs. [Ba/Fe] space for the early Galaxy
复制标题
早期星系 [Sr/Ba] 与 [Ba/Fe] 空间中 r 过程材料的污染轨迹
DOI：
10.1088/1674-4527/21/5/111
复制
发表时间：
2021-06
影响因子：
1.8
通讯作者：
Zhang Bo
中科院分区：
文献类型：
--
作者：
Han Wan-Qiang;Yang Guo-Chao;Zhang Lu;Cui Wen-Yuan;Niu Ping;Wen Fang;Zhang Bo
在银河系早期，极贫金属（EMP）恒星的元素丰度包含了中子捕获核合成和化学富集历史的丰富信息。本文研究了EMP恒星在[Sr/Ba]和[Ba/Fe]空间中Sr和Ba的丰度特征。我们发现电磁脉冲恒星的分布区域有三个边界。弱r过程星CS 22897-008位于上端，主r过程星位于右端。在分布区右侧边界附近，有一条铁正态带。对于带内的EMP恒星，铁元素主要来源于正常的大质量恒星。低锶星（[Sr/Fe]≤- 0.3）分布在铁正带的左下方区域，它们的铁部分来源于及时盘存。我们发现分布区的下边界的形成是由于主r过程物质的污染，右边界的形成可以用弱r-和主r过程物质的结合来解释。此外，左边界的形成是由于弱r过程物质的污染。虽然[Sr/Ba]比值与弱r过程物质的相对重要性有关，但EMP恒星[Sr/Ba]比值的散射主要取决于弱r过程的丰度比。
In the early Galaxy, elemental abundances of the extremely metal-poor (EMP) stars contain abundant information about the neutron-capture nucleosynthesis and the chemical enrichment history. In this work, we study the abundance characteristics of Sr and Ba for the EMP stars in the [Sr/Ba] vs. [Ba/Fe] space. We find that there are three boundaries for the distribution region of the EMP stars. The weak r-process star CS 22897–008 lies on the upper end and the main r-process stars lie on the right end of the region. Near the right boundary of the distribution region, there is an Fe-normal belt. For the EMP stars in the belt, element Fe dominantly originates from the normal massive stars. The low-Sr stars ([Sr/Fe]≤−0.3) distribute in the region of the lower left of the Fe-normal belt and their Fe should originate partly from the prompt inventory. We find that the formation of the lower boundary of the distribution region is due to the pollution of the main r-process material and the formation of the right boundary could be explained by the combination of the weak r- and main r-process material. Furthermore, the formation of the left boundary is due to the pollution of the weak r-process material. Although the [Sr/Ba] ratios are related to the relative importance of the weak r-process material, the scatter of [Sr/Ba] ratios for the EMP stars mainly depends on the abundance ratio of the weak r-process.
登录
查看更多内容
DOI：
10.1086/300289
发表时间：
1998-04
期刊：
The Astronomical Journal
影响因子：
--
作者：
A. McWilliam
通讯作者：
A. McWilliam
影响因子：
6.5
作者：
L. Mashonkina;N. Christlieb;P. Barklem;V. Hill;T. Beers;A. Velichko
通讯作者：
L. Mashonkina;N. Christlieb;P. Barklem;V. Hill;T. Beers;A. Velichko
DOI：
10.1086/503195
发表时间：
2006-02
期刊：
The Astrophysical Journal
影响因子：
--
作者：
S. Honda;W. Aoki;Y. Ishimaru;S. Wanajo;S. Ryan
通讯作者：
S. Honda;W. Aoki;Y. Ishimaru;S. Wanajo;S. Ryan
DOI：
10.1088/0004-637x/798/2/110
发表时间：
2015-01
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Haining Li;Gang Zhao;N. Christlieb;Liang-Yao Wang;Wei Wang;Yong Zhang;Yong-Hui Hou;Hailong Yuan-Hailong
通讯作者：
Haining Li;Gang Zhao;N. Christlieb;Liang-Yao Wang;Wei Wang;Yong Zhang;Yong-Hui Hou;Hailong Yuan-Hailong
DOI：
10.1086/322367
发表时间：
2001-06
期刊：
The Astrophysical Journal
影响因子：
--
作者：
Y. Qian;G. Wasserburg
通讯作者：
Y. Qian;G. Wasserburg