{"title":"用于未来托卡马克硬X射线诊断的PMT信号传输","authors":"P. Nowak vel Nowakowski, D. Makowski, W. Walewski","doi":"10.1007/s10894-022-00334-8","DOIUrl":null,"url":null,"abstract":"<div><p>A pair of a scintillator and a Photomultiplier Tube (PMT) is often used as a Hard X-Ray (HXR) radiation detector in existing tokamaks such as JET, EAST, COMPASS or ASDEX-U. Future nuclear fusion reactors such as ITER or DEMO will use more powerful magnets and confine a larger volume of hot plasma. Placement of the detectors used for plasma diagnostic will be constrained by high temperatures, magnetic fields and ionizing radiation present near the tokamak vessel. It might be necessary to move detectors away from tokamak to a safer location. This might generate problems with pulse discrimination and transmission of the signal. In the case of the ITER tokamak, sensitive electronics such as digitizers cannot be installed close to the reactor due to harsh environmental conditions. A new approach to component placement is needed to protect those devices. The PMT signal will be transmitted via an over 100 m long coaxial cable to the digitizer located in the adjacent diagnostic building. The long cables will introduce additional signal attenuation. Also, the RF noise from the tokamak environment can couple into the signal. To improve the signal-to-noise ratio a dedicated PMT amplifier with a high output range (from + 1.5 to − 11 V) was proposed.The paper presents issues with signal transmission in HXR diagnostic systems and includes a discussion on the methodology of PMT signal transmission in the conditions of the future tokamaks. A proposal of guidelines for selection of the signal chain components and design of a dedicated PMT amplifier is part of this paper.</p></div>","PeriodicalId":634,"journal":{"name":"Journal of Fusion Energy","volume":null,"pages":null},"PeriodicalIF":1.9000,"publicationDate":"2022-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10894-022-00334-8.pdf","citationCount":"2","resultStr":"{\"title\":\"PMT Signal Transmission for Hard X-Ray Diagnostics of Future Tokamaks\",\"authors\":\"P. Nowak vel Nowakowski, D. Makowski, W. Walewski\",\"doi\":\"10.1007/s10894-022-00334-8\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>A pair of a scintillator and a Photomultiplier Tube (PMT) is often used as a Hard X-Ray (HXR) radiation detector in existing tokamaks such as JET, EAST, COMPASS or ASDEX-U. Future nuclear fusion reactors such as ITER or DEMO will use more powerful magnets and confine a larger volume of hot plasma. Placement of the detectors used for plasma diagnostic will be constrained by high temperatures, magnetic fields and ionizing radiation present near the tokamak vessel. It might be necessary to move detectors away from tokamak to a safer location. This might generate problems with pulse discrimination and transmission of the signal. In the case of the ITER tokamak, sensitive electronics such as digitizers cannot be installed close to the reactor due to harsh environmental conditions. A new approach to component placement is needed to protect those devices. The PMT signal will be transmitted via an over 100 m long coaxial cable to the digitizer located in the adjacent diagnostic building. The long cables will introduce additional signal attenuation. Also, the RF noise from the tokamak environment can couple into the signal. To improve the signal-to-noise ratio a dedicated PMT amplifier with a high output range (from + 1.5 to − 11 V) was proposed.The paper presents issues with signal transmission in HXR diagnostic systems and includes a discussion on the methodology of PMT signal transmission in the conditions of the future tokamaks. A proposal of guidelines for selection of the signal chain components and design of a dedicated PMT amplifier is part of this paper.</p></div>\",\"PeriodicalId\":634,\"journal\":{\"name\":\"Journal of Fusion Energy\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.9000,\"publicationDate\":\"2022-08-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s10894-022-00334-8.pdf\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Fusion Energy\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10894-022-00334-8\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"NUCLEAR SCIENCE & TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Fusion Energy","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10894-022-00334-8","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
PMT Signal Transmission for Hard X-Ray Diagnostics of Future Tokamaks
A pair of a scintillator and a Photomultiplier Tube (PMT) is often used as a Hard X-Ray (HXR) radiation detector in existing tokamaks such as JET, EAST, COMPASS or ASDEX-U. Future nuclear fusion reactors such as ITER or DEMO will use more powerful magnets and confine a larger volume of hot plasma. Placement of the detectors used for plasma diagnostic will be constrained by high temperatures, magnetic fields and ionizing radiation present near the tokamak vessel. It might be necessary to move detectors away from tokamak to a safer location. This might generate problems with pulse discrimination and transmission of the signal. In the case of the ITER tokamak, sensitive electronics such as digitizers cannot be installed close to the reactor due to harsh environmental conditions. A new approach to component placement is needed to protect those devices. The PMT signal will be transmitted via an over 100 m long coaxial cable to the digitizer located in the adjacent diagnostic building. The long cables will introduce additional signal attenuation. Also, the RF noise from the tokamak environment can couple into the signal. To improve the signal-to-noise ratio a dedicated PMT amplifier with a high output range (from + 1.5 to − 11 V) was proposed.The paper presents issues with signal transmission in HXR diagnostic systems and includes a discussion on the methodology of PMT signal transmission in the conditions of the future tokamaks. A proposal of guidelines for selection of the signal chain components and design of a dedicated PMT amplifier is part of this paper.
期刊介绍:
The Journal of Fusion Energy features original research contributions and review papers examining and the development and enhancing the knowledge base of thermonuclear fusion as a potential power source. It is designed to serve as a journal of record for the publication of original research results in fundamental and applied physics, applied science and technological development. The journal publishes qualified papers based on peer reviews.
This journal also provides a forum for discussing broader policies and strategies that have played, and will continue to play, a crucial role in fusion programs. In keeping with this theme, readers will find articles covering an array of important matters concerning strategy and program direction.