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Measurement of the $Ag (n, γ)$ cross section up to stellar s-process temperatures at the CSNS Back-n

Di Sun ^1,2, Zhendong An ^1,3,4,*, Wei Jiang^5,6, Yu-gang Ma^3,4, Liu Li^2,†, Jie Ren^7,‡, Xichao Ruan⁷, Jingyu Tang ⁸, Ruirui Fan^5,6 et al. (The CSNS Back-n Collaboration)

Ruirui Fan^5,6, Hongwei Wang^10,9, Wenqing Shen^10,9, Jingyi Zhang ¹¹, Ruoran Bai¹², Shaokun Liu ¹³, Yubing Li^1,14, Cheng Li¹⁴, Chenchen Guo¹⁵, Hao Liang^1,15, Junheng Hu ^1,15, Ting Liu ^1,15, Yi Sui ^1,16, Xiankai Li¹⁶, Xinxiang Li¹⁶, Wen Luo ¹⁶, Yaju Chen¹⁶, Wen Xie¹⁶, Zhouji Liao¹⁶, Xinrong Hu¹⁷, Chunwang Ma ^18,19, Han Yi^5,6, Yonghao Chen ^5,6, Qiang Li^5,6, Zhixin Tan^5,6, and Hantao Jing^5,6 (The CSNS Back-n Collaboration)

¹Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
²College of Physical Science and Technology, Shenyang Normal University, Shenyang 110034, China
³Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Department of Nuclear Science and Technology, Institute of Modern Physics, Fudan University, Shanghai 200433, China
⁴Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University, Shanghai 200438, China
⁵Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
⁶Spallation Neutron Source Science Center, Dongguan 523803, China
⁷Key Laboratory of Nuclear Data, China Institute of Atomic Energy, Beijing 102413, China
⁸School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230027, China
⁹Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
¹⁰Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
¹¹Department of Astronomy, Tsinghua University, Beijing 100084, China
¹²School of Physics, Sun Yat-sen University, Guangzhou 510275, China
¹³School of Physics and Astronomy, Sun Yat-sen University, Zhuhai 519082, China
¹⁴Guangxi Key Laboratory of Nuclear Physics and Technology, College of Physics and Technology, Guangxi Normal University, Guilin 541004, China
¹⁵Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
¹⁶School of Nuclear Science and Technology, University of South China, Hengyang 421001, China
¹⁷Chengdu University of Technology, Chengdu 610059, China
¹⁸Institute of Nuclear Science and Technology, Henan Academy of Sciences, Zhengzhou 450046, China
¹⁹College of Physics, Centre for Theoretical Physics, Henan Normal University, Xinxiang 453007, China

^*Contact author: anzhendong@impcas.ac.cn
^†Contact author: liliu2020@synu.edu.cn
^‡Contact author: renjie@ciae.ac.cn

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Phys. Rev. Research 7, 043348 – Published 30 December, 2025

DOI: https://doi.org/10.1103/1c5x-8d44

Abstract

The $(n, γ)$ cross section of silver is crucial for the nucleosynthesis process of nuclear astrophysics, the design of silver-indium-cadmium absorber rod in the nuclear reactors, and neutron resonance capture analysis for determining the elemental and isotopic composition of cultural heritage. The high-precision $Ag (n, γ)$ cross section was measured from 1 eV to 1 MeV at the Back-n facility of the Chinese Spallation Neutron Source using the time-of-flight method and pulse height weighting technique. The resonance parameters were accurately extracted in the resolved resonance region by the multilevel multichannel $R$ -matrix code sammy. The talys code was used to describe the average cross sections in the unresolved resonance region, and the Maxwellian-averaged cross sections (MACSs) of ${}^{107}{Ag}$ and ${}^{109}{Ag}$ were further given in the 5–100 keV range. The MACS values at $k T = 30 keV$ for ${}^{107}{Ag}$ $(887 \pm 89 mb)$ and ${}^{109}{Ag}$ $(903 \pm 90 mb)$ are slightly higher than the recommended values in the Karlsruhe Astrophysical Database of Stellar Nucleosynthesis.

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Phys. Rev. Research 7, 043348– Published 30 December, 2025

Vol. 7, Iss. 4 — December - December 2025

Received 1 July 2025
Accepted 13 November 2025

DOI: https://doi.org/10.1103/1c5x-8d44

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Measurement of the $Ag (n, γ)$ cross section up to stellar s-process temperatures at the CSNS Back-n

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Measurement of the Ag(n, γ) cross section up to stellar s-process temperatures at the CSNS Back-n

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References (87)

Measurement of the $Ag (n, γ)$ cross section up to stellar s-process temperatures at the CSNS Back-n