裂变在r过程质量敏感性研究中的作用
近日，兰州大学牛一斐团队研究了裂变在r过程质量敏感性研究中的作用。该项研究成果发表在2025年9月23日出版的《中国物理C》杂志上。
在不同的天体物理情景下，人们对单个核质量对r-过程稀土峰丰度的影响进行了灵敏度研究。最具影响力的原子核主要分布在核图上的两个区域：一个距离稳定区20-30个中子（定义为区域I），另一个距离稳定区7-15个中子（定义为区域II），正如之前在报道的那样（Lett.[j] .地球科学进展，2016,32(5):559 - 561）。
研究组通过关注裂变在质量敏感性研究中的作用来扩展他们的分析。结果表明，在涉及裂变的天体物理场景中，由于大量裂变碎片沉积在稀土质量区，导致I区原子核的灵敏度降低。然而，在核合成的后期阶段，由于裂变的贡献减少，II区的原子核保持了高灵敏度。这项研究突出了裂变对r过程丰度对核质量敏感性的影响，有助于提高对稀土峰形成机制的认识。
附：英文原文
Title: The Role of Fission in Mass Sensitivity Study of the r-process
Author: Yi Wei Hao, Yi Fei Niu, Zhong Ming Niu
Issue&Volume: 2025-09-23
Abstract: A sensitivity study was performed to investigate the impact of individual nuclear masses on r-process rare-earth peak abundances in different astrophysical scenarios. The most impactful nuclei are primarily distributed in two regions on the nuclear chart: one located 20-30 neutrons away from stability (defined as region I) and another 7-15 neutrons away from stability (defined as region II), as previously reported in Phys. Lett. B 844, 138092 (2023). In this work, we extend our analysis by focusing on the role of fission in the mass sensitivity study. The results show that in astrophysical scenarios involving fission, the sensitivity of nuclei in region I is diminished due to the deposition of a large number of fission fragments in the rare-earth mass region. However, nuclei in region II retain high sensitivity because the contribution of fission decreases in the later stages of nucleosynthesis. This study highlights the impact of fission on the sensitivity of r-process abundances to nuclear masses and helps to enhance the understanding of the rare-earth peak formation mechanism.
DOI: 10.1088/1674-1137/adfe55
Source: http://hepnp.ihep.ac.cn/article/doi/10.1088/1674-1137/adfe55