Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS
The nuclear data of Th is primary interest for the thorium-uranium (Th-U) fuel cycle, and its nuclear data accuracy is related to the conversion performance of Th-U fuel cycle. Based on the photo-neutron source for the thorium molten salt reactor (TMSR-PNS), the total cross section (TCS) of ThO2 wa...
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| Format: | Article |
| Language: | English |
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Editorial Board of Atomic Energy Science and Technology
2022-01-01
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| Series: | Yuanzineng kexue jishu |
| Subjects: | |
| Online Access: | https://www.aest.org.cn/CN/10.7538/yzk.2021.youxian.0434 |
| _version_ | 1811304968254128128 |
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| author | HU Jifeng;WANG Xiaohe;JIANG Bing;HAN Jianlong;CHEN Jingen;CAI Xiangzhou |
| author_facet | HU Jifeng;WANG Xiaohe;JIANG Bing;HAN Jianlong;CHEN Jingen;CAI Xiangzhou |
| author_sort | HU Jifeng;WANG Xiaohe;JIANG Bing;HAN Jianlong;CHEN Jingen;CAI Xiangzhou |
| collection | DOAJ |
| description | The nuclear data of Th is primary interest for the thorium-uranium (Th-U) fuel cycle, and its nuclear data accuracy is related to the conversion performance of Th-U fuel cycle. Based on the photo-neutron source for the thorium molten salt reactor (TMSR-PNS), the total cross section (TCS) of ThO2 was measured by the transmission method for the high purity thorium oxide (ThO2) samples. ThO2 samples which the thicknesses were respectively 0.9 cm and 0.608 cm were made by pressing and sintering process at 1 800 ℃. Based on the different pulse shapes of neutrons and γ-rays (n/γ) signal from the lithium iodide (LiI) scintillator detector used for the time-of-flight (TOF) calculation, γ-rays were identified by pulse shape discrimination (PSD) method to reduce the interference of the measured cross section. Combined with the trough position of TOF spectrum and its corresponding energy for the calibration targets of Ag, In and Cd, the flight distance was fitted to be 5.899 m, so as to convert TOF spectrum of neutrons into energy spectrum. Energy spectrum of 10 cm thickness boracic polythene sample was measured to deduct the influence of the scattering neutron from the background. According to the measured neutron leakage spectrum with or without ThO2 sample, experimental data of TCS for ThO2 were obtained. TCS of 16O from ENDF/B-Ⅶ.1 was deducted from TCS of ThO2 and TCS of Th was obtained. Combined with error of the sample purity and thickness, the fitting flight distance, relative standard deviation of TCS for 16O from ENDF/B-Ⅶ.1, and experimental statistical error, the uncertainty of experimental data were calculeted to be 3.25%-4.51% in the energy range from 0.02 to 0.1 eV. The results show that the measured data of TCS of Th are good agreement with the evaluated data of ENDF/B-Ⅶ.1 in the energy range from 0.02 to 0.1 eV. In the thermal energy range (E<0.02 eV), thermal neutron scattering (TNS) effect of Th in ThO2, which is characterized by Bragg-edges, is evident and similar for U in UO2 in ENDF/B-Ⅶ.1. |
| first_indexed | 2024-04-13T08:16:54Z |
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| id | doaj.art-78dacfa2cb8c4cc5a6ec82a9f2816535 |
| institution | Directory Open Access Journal |
| issn | 1000-6931 |
| language | English |
| last_indexed | 2024-04-13T08:16:54Z |
| publishDate | 2022-01-01 |
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| spelling | doaj.art-78dacfa2cb8c4cc5a6ec82a9f28165352022-12-22T02:54:45ZengEditorial Board of Atomic Energy Science and TechnologyYuanzineng kexue jishu1000-69312022-01-015616167Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNSHU Jifeng;WANG Xiaohe;JIANG Bing;HAN Jianlong;CHEN Jingen;CAI Xiangzhou 0Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China;CAS Innovative Academies in TMSR Energy System, Shanghai 201800, China;University of Chinese Academy of Sciences, Beijing 100049, China The nuclear data of Th is primary interest for the thorium-uranium (Th-U) fuel cycle, and its nuclear data accuracy is related to the conversion performance of Th-U fuel cycle. Based on the photo-neutron source for the thorium molten salt reactor (TMSR-PNS), the total cross section (TCS) of ThO2 was measured by the transmission method for the high purity thorium oxide (ThO2) samples. ThO2 samples which the thicknesses were respectively 0.9 cm and 0.608 cm were made by pressing and sintering process at 1 800 ℃. Based on the different pulse shapes of neutrons and γ-rays (n/γ) signal from the lithium iodide (LiI) scintillator detector used for the time-of-flight (TOF) calculation, γ-rays were identified by pulse shape discrimination (PSD) method to reduce the interference of the measured cross section. Combined with the trough position of TOF spectrum and its corresponding energy for the calibration targets of Ag, In and Cd, the flight distance was fitted to be 5.899 m, so as to convert TOF spectrum of neutrons into energy spectrum. Energy spectrum of 10 cm thickness boracic polythene sample was measured to deduct the influence of the scattering neutron from the background. According to the measured neutron leakage spectrum with or without ThO2 sample, experimental data of TCS for ThO2 were obtained. TCS of 16O from ENDF/B-Ⅶ.1 was deducted from TCS of ThO2 and TCS of Th was obtained. Combined with error of the sample purity and thickness, the fitting flight distance, relative standard deviation of TCS for 16O from ENDF/B-Ⅶ.1, and experimental statistical error, the uncertainty of experimental data were calculeted to be 3.25%-4.51% in the energy range from 0.02 to 0.1 eV. The results show that the measured data of TCS of Th are good agreement with the evaluated data of ENDF/B-Ⅶ.1 in the energy range from 0.02 to 0.1 eV. In the thermal energy range (E<0.02 eV), thermal neutron scattering (TNS) effect of Th in ThO2, which is characterized by Bragg-edges, is evident and similar for U in UO2 in ENDF/B-Ⅶ.1.https://www.aest.org.cn/CN/10.7538/yzk.2021.youxian.0434tmsr-pnstotal cross sectiontho2transmission method |
| spellingShingle | HU Jifeng;WANG Xiaohe;JIANG Bing;HAN Jianlong;CHEN Jingen;CAI Xiangzhou Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS Yuanzineng kexue jishu tmsr-pns total cross section tho2 transmission method |
| title | Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS |
| title_full | Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS |
| title_fullStr | Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS |
| title_full_unstemmed | Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS |
| title_short | Measurement of Neutron Total Cross Section of Th in 0.008-0.1 eV at TMSR-PNS |
| title_sort | measurement of neutron total cross section of th in 0 008 0 1 ev at tmsr pns |
| topic | tmsr-pns total cross section tho2 transmission method |
| url | https://www.aest.org.cn/CN/10.7538/yzk.2021.youxian.0434 |
| work_keys_str_mv | AT hujifengwangxiaohejiangbinghanjianlongchenjingencaixiangzhou measurementofneutrontotalcrosssectionofthin000801evattmsrpns |