Article title: Measurements of the ¹⁹⁷Au (n, γ) cross section up to 100 keV at the CSNS Back-n facility

文章题目：CSNS Back-n装置100 keV以下¹⁹⁷Au (n, γ)截面的测量

DOI:  10.1007/s41365-021-00931-w

One sentence summary:

一句话概要：

The C6D6 detectors system for the ¹⁹⁷Au (n, γ) reaction cross section measurement has been successfully carried out at Back-n beamline and good results have been obtained, which check the detector system’s accuracy and shows promising outcomes of future neutron capture cross section measurements.

利用Back-n的C6D6 探测系统已成功展开了197Au的中子俘获截面的测量，并取得了很好的结果；它检测了这套探测系统的可靠性与展示了未来继续在Back-n上展开中子俘获截面测量的广阔前景。

http://www.nst.sinap.ac.cn/newsDetails/112/18752/en/

The Novelty (What)

创新性（主要内容）

This study verified the effectiveness of the upgraded CSNS Back-n neutron beamline detection system for neutron capture cross-section measurements using gold (¹⁹⁷Au (n, γ)). The new setup included C₆D₆ detectors and Li-Si flux monitor,  the pulse height weighting technique (PHWT) detection technology was used to analysis the data. The results proved that the ¹⁹⁷Au (n, γ) reaction cross section measured with neutron energies ranging from 1 eV to 100 keV is consistent with the latest standard evaluations data. Meanwhile, the findings indicated a promising less than 2% statistical uncertainty for the ¹⁹⁷Au (n, γ) reaction cross section measured. Therefore, it is evident that the CSNS Back-n neutron beamline facility enhancement proposed in this study would benefit future characterization and the study of synthesis of heavy elements.

本研究验证了改进后的CSNS back-n中子束线探测系统在gold (¹⁹⁷Au (n, γ))俘获截面测量中的有效性。 新的装置包括C₆D₆探测器和脉冲高度加权技术(PHWT)探测技术。 结果表明,用1 eV到100 keV的中子能量测量的¹⁹⁷Au (n, γ)反应截面与现有探测器的最新标准评价是一致的。 同时,测量的¹⁹⁷Au (n, γ)反应截面的统计不确定度小于2%。 因此，本研究提出的CSNS back-n中子束线装置的改进将有利于重元素的表征和合成。

The Background (Why)

研究背景（主要原因）

Neutron-induced reactions have long been used to characterize and synthesize heavy elements. Such techniques have been inspired by the naturally occurring slow neutron capture process (s process) in stars. At present, most neutron capture cross section measurements only have one capture criterion for the 197Au (n, γ) reaction with energy ranging from thermal to 2.5 MeV. Hence, this study proposed integrating C₆D₆ detectors and PHWT detection technology with the CSNS Back-n neutron beamline. The overall feasibility of the experimental setup was determined by cross-referencing the data with the standard neutron capture cross-section database.

中子诱导反应早已被用来表征和合成重元素。 这类技术受到了恒星中自然发生的慢中子俘获过程（s过程）的启发。 目前，多数中子俘获截面测量只有197Au（n，γ），中子能量从热中子到2.5meV，这一个俘获判据。 因此，本研究提出将C₆D₆探测器和PHWT探测技术与CSNS back-n中子束线集成。 通过与标准中子俘获截面数据库的数据交叉引用，确定了实验设置的总体可行性。

The SDG impact (Big Why)

SDG影响力（研究意义）

Neutrons have long played an essential role in engineering materials for nuclear reactors, along with material characterization. As the demand for electric energy grows, so does the demand for potential alternative energy production sources, one of which is nuclear power. Thus, there is a constant need to advance and enhance existing nuclear detection and imaging technology (UN SDG 9: Industry, innovation and infrastructure). The findings of this study could serve as a reference to improve the performance of the current Back-n neutron beamline facility for better heavy chemical elements characterization and data analysis.

长期以来，中子在核反应堆的工程材料以及材料表征中起着至关重要的作用。 随着对电能的需求增长，对潜在的替代能源生产来源的需求也在增长，其中之一就是核电。 因此，不断需要推进和加强现有的核探测和成像技术（联合国可持续发展目标9：工业、创新和基础设施）。 本研究结果可为改进现有back-n中子束线装置的重元素表征和数据分析提供参考。