Investigation of vacuum melting technique for low background titanium
BackgroundThe expected signal rate of rare decay experiments, such as instance dark matter and neutrino less double beta decay experiments, is extremely low, which requires that the detector building materials have extremely low radioactivity. Low radioactive background control is one of the essent...
| Main Authors: | , , , , , , , , |
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| Format: | Article |
| Language: | zho |
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Science Press
2022-11-01
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| Series: | He jishu |
| Subjects: | |
| Online Access: | https://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2022.hjs.45.110201&lang=zh |
| _version_ | 1811169608969748480 |
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| author | ZHANG Tao HAN Ke LIU Jianglai MENG Yue YAO Yukun WANG Siguang LI Bobo LIU Yinqi PEI Teng |
| author_facet | ZHANG Tao HAN Ke LIU Jianglai MENG Yue YAO Yukun WANG Siguang LI Bobo LIU Yinqi PEI Teng |
| author_sort | ZHANG Tao |
| collection | DOAJ |
| description | BackgroundThe expected signal rate of rare decay experiments, such as instance dark matter and neutrino less double beta decay experiments, is extremely low, which requires that the detector building materials have extremely low radioactivity. Low radioactive background control is one of the essential works in the rare decay experiments. 226Ra and 228Ra produced in the early decay chain of 238U and 232Th have low boiling point and high vapor pressure, removing the element Ra can break the 238U decay chain and keep a low radioactivity of 232Th-late for a long time.PurposeThis study aims to investigate vacuum melting technique for low background titanium to reduce the impurity of isotopes that have negative impact on rare decay experiments and creating a low background environment for the detector running.MethodsFirstly, the low background material samples were acquired by manual separation of radionuclides using physical and chemical methods. Then, radioactive impurity elements, such as K, Cs, Ra, Pb, Po and Rn with low boiling point and high vapor pressure, were volatilized in environment with high temperature and high vacuum level. Finally, radioactivity of these testing samples were measured by two sets of high-purity germanium γ spectrometer with measurement time extended to 7 days.ResultsMeasurement results show signs of removal of radioactive isotopes by smelting-vacuum method, and the impurity in pure titanium smelted in vacuum electron beam furnace can reach the levels of (0.13±0.69) mBq∙kg-1 for 232Th-228Ac, and (0.07±0.29) mBq∙kg-1 for 238U-222Rn, respectively.ConclusionsThe smelting-vacuum method could provide reliable low background material for the container of the next generation PandaX detector. |
| first_indexed | 2024-04-10T16:45:15Z |
| format | Article |
| id | doaj.art-429c2c8409e0438aa0c00175526b6823 |
| institution | Directory Open Access Journal |
| issn | 0253-3219 |
| language | zho |
| last_indexed | 2024-04-10T16:45:15Z |
| publishDate | 2022-11-01 |
| publisher | Science Press |
| record_format | Article |
| series | He jishu |
| spelling | doaj.art-429c2c8409e0438aa0c00175526b68232023-02-08T01:05:03ZzhoScience PressHe jishu0253-32192022-11-01451111020111020110.11889/j.0253-3219.2022.hjs.45.1102010253-3219（2022）11-0022-09Investigation of vacuum melting technique for low background titaniumZHANG Tao0HAN Ke1LIU Jianglai2MENG Yue3YAO Yukun4WANG Siguang5LI Bobo6LIU Yinqi7PEI Teng8Sichuan Research Institute, Shanghai Jiao Tong University, Chengdu 610213, ChinaSichuan Research Institute, Shanghai Jiao Tong University, Chengdu 610213, ChinaSichuan Research Institute, Shanghai Jiao Tong University, Chengdu 610213, ChinaSichuan Research Institute, Shanghai Jiao Tong University, Chengdu 610213, ChinaSichuan Research Institute, Shanghai Jiao Tong University, Chengdu 610213, ChinaSchool of Physics, State Key Laboratory of Nuclear Physics and Technology and Center for High Energy Physics, Peking University, Beijing 100871, ChinaLuoyang Shuangrui Titanium Precision Casting Co., Ltd., Luoyang 471000, ChinaLuoyang Shuangrui Titanium Precision Casting Co., Ltd., Luoyang 471000, ChinaLuoyang Shuangrui Titanium Precision Casting Co., Ltd., Luoyang 471000, ChinaBackgroundThe expected signal rate of rare decay experiments, such as instance dark matter and neutrino less double beta decay experiments, is extremely low, which requires that the detector building materials have extremely low radioactivity. Low radioactive background control is one of the essential works in the rare decay experiments. 226Ra and 228Ra produced in the early decay chain of 238U and 232Th have low boiling point and high vapor pressure, removing the element Ra can break the 238U decay chain and keep a low radioactivity of 232Th-late for a long time.PurposeThis study aims to investigate vacuum melting technique for low background titanium to reduce the impurity of isotopes that have negative impact on rare decay experiments and creating a low background environment for the detector running.MethodsFirstly, the low background material samples were acquired by manual separation of radionuclides using physical and chemical methods. Then, radioactive impurity elements, such as K, Cs, Ra, Pb, Po and Rn with low boiling point and high vapor pressure, were volatilized in environment with high temperature and high vacuum level. Finally, radioactivity of these testing samples were measured by two sets of high-purity germanium γ spectrometer with measurement time extended to 7 days.ResultsMeasurement results show signs of removal of radioactive isotopes by smelting-vacuum method, and the impurity in pure titanium smelted in vacuum electron beam furnace can reach the levels of (0.13±0.69) mBq∙kg-1 for 232Th-228Ac, and (0.07±0.29) mBq∙kg-1 for 238U-222Rn, respectively.ConclusionsThe smelting-vacuum method could provide reliable low background material for the container of the next generation PandaX detector.https://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2022.hjs.45.110201&lang=zhlow backgroundrare decay experimentdark matterneutrinoless double beta decayvacuum melting |
| spellingShingle | ZHANG Tao HAN Ke LIU Jianglai MENG Yue YAO Yukun WANG Siguang LI Bobo LIU Yinqi PEI Teng Investigation of vacuum melting technique for low background titanium He jishu low background rare decay experiment dark matter neutrinoless double beta decay vacuum melting |
| title | Investigation of vacuum melting technique for low background titanium |
| title_full | Investigation of vacuum melting technique for low background titanium |
| title_fullStr | Investigation of vacuum melting technique for low background titanium |
| title_full_unstemmed | Investigation of vacuum melting technique for low background titanium |
| title_short | Investigation of vacuum melting technique for low background titanium |
| title_sort | investigation of vacuum melting technique for low background titanium |
| topic | low background rare decay experiment dark matter neutrinoless double beta decay vacuum melting |
| url | https://www.hjs.sinap.ac.cn/thesisDetails#10.11889/j.0253-3219.2022.hjs.45.110201&lang=zh |
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