PMT Signal Transmission for Hard X-Ray Diagnostics of Future Tokamaks

IF 1.9 4区工程技术 Q1 NUCLEAR SCIENCE & TECHNOLOGY Journal of Fusion Energy Pub Date : 2022-08-10 DOI:10.1007/s10894-022-00334-8

P. Nowak vel Nowakowski, D. Makowski, W. Walewski

{"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}

引用次数: 2

Abstract

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.

Abstract Image

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

用于未来托卡马克硬X射线诊断的PMT信号传输

一对闪烁体和一个光电倍增管(PMT)在现有的托卡马克中经常用作硬x射线(HXR)辐射探测器，如JET, EAST, COMPASS或ASDEX-U。未来的核聚变反应堆，如ITER或DEMO，将使用更强大的磁铁，并限制更大体积的热等离子体。用于等离子体诊断的探测器的放置将受到高温、磁场和托卡马克容器附近电离辐射的限制。也许有必要把探测器从托卡马克移到一个更安全的地方。这可能会对脉冲识别和信号传输产生问题。以ITER托卡马克为例，由于环境条件恶劣，数字化仪等敏感电子设备无法安装在反应堆附近。需要一种新的组件放置方法来保护这些设备。PMT信号将通过超过100米长的同轴电缆传输到位于邻近诊断大楼的数字化仪。长电缆会带来额外的信号衰减。此外，来自托卡马克环境的射频噪声可以耦合到信号中。为了提高信噪比，提出了一种高输出范围(+ 1.5 ~ - 11 V)的专用PMT放大器。本文提出了HXR诊断系统中信号传输的问题，并讨论了未来托卡马克条件下PMT信号传输的方法。本文提出了信号链元件选择和专用PMT放大器设计的指导方针。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Journal of Fusion Energy 工程技术-核科学技术

CiteScore

2.20

自引率

0.00%

发文量

审稿时长

2.3 months

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.