物理学报2026，Vol.75Issue(2)：57-64,8.DOI:10.7498/aps.75.20251263
1-100 eV能区169Tm中子全截面测量与共振参数分析
Measurement of neutron total cross sections and resonance parameters analysis of 169Tm in the region from 1 eV to 100 eV
摘要
Abstract
The neutron total cross section is one of the most fundamental nuclear data.In the low-energy resonance region,discrepancies among measurements arise from experimental backgrounds,sample self-shielding,and instrumental broadening,which complicate the precise determination of cross sections.In this work,the neutron total cross section of 169Tm is measured at the Back-n facility of the China Spallation Neutron Source(CSNS).Wing-shaped lithium glass detectors are used to record the transmitted neutron signals from samples with thicknesses of 0.5 mm and 4.5 mm.The raw data are processed,including time-of-flight correction and normalization to the incident proton number,to account for the fluctuations in the proton beam intensity.The in-beam γ background is quantified using the saturated resonance absorption technique with glass scintillators.After background subtraction,transmission and total cross-section data are obtained in an energy range of 1-100 eV.The measured spectra are analyzed using the SAMMY code within the framework of the R-matrix.Neutron capture yield data are incorporated to improve the reliability of the extracted resonance parameters.For the resonance near 8 eV,the Γγ is set to the library average value of 86 meV.The resonance energy is determined to be 8.037 eV,consistent with the recently reported resonance by I.Knapová et al.and the neutron widths for both total spin states are evaluated.Based on the extracted parameters,the neutron total cross section of 169Tm is reconstructed using the Reich-Moore approximation.The reconstructed cross section shows good agreement with those recommended by ENDF/B-Ⅷ.1 library,confirming the reliability of the resonance parameters extracted from the capture-transmission measurements.Overall,the present measurements and analysis provide a set of resonance parameters for 169Tm,enhancing the experimental foundation for both nuclear physics research and nuclear industry. The datasets presented in this paper,including the neutron transmission,neutron total cross section,and resonance parameters are openly available at https://www.doi.org/10.57760/sciencedb.j00213.00192.关键词
中子透射率/中子全截面/共振参数/R矩阵Key words
neutron transmission/neutron total cross section/resonance parameters/R-matrix引用本文复制引用
杨皓岚,孙琪,刘颖一,罗忠献,黄翰雄,薛洁明,任杰,陈永浩,阮锡超,王金成,鲍杰,樊瑞睿,蒋伟..1-100 eV能区169Tm中子全截面测量与共振参数分析[J].物理学报,2026,75(2):57-64,8.基金项目
国家自然科学基金(批准号:12475308)、国家重点研发计划(批准号:2023YFA1606603)和稳定支持基础科研计划(批准号:BJ010261223282)资助的课题. Project supported by the National Natural Science Foundation of China(Grant No.12475308),the National Key Research Program of China(Grant No.2023YFA1606603),and the Continuous-Support Basic Scientific Research Project,China(Grant No.BJ010261223282). （批准号:12475308）
