Monitoring Reactors for Nuclear Safeguards with T2K Technology

利用 T2K 技术监测反应堆的核保障

• 批准号: ST/M000168/1
• 负责人: Jonathon Coleman
• 金额: $ 15.19万
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FM000168%2F1
• 关键词: Monitoring; Reactors; Nuclear; Safeguards; T2K

Over the last 6-7 years STFC has lead an academic consortium that has developed a large neutrino detector as part of an international experiment in Japan called T2K. The Liverpool group believe that the technology developed for this international work can be adapted to make a small footprint, highly reliable, detector to characterise the anti-neutrinos that are emitted from the core of operational nuclear fission reactors. Measuring the quantity and energy level of anti-neutrino emissions from a power station when correlated to the reactor power output is a very effective way of detecting undeclared shut-downs and whether or not high grade nuclear material has been covertly removed from the process, and so an ideal way for the IAEA to detect malpractice.The detector built for the T2K experiment is a sampling Electromagnetic Calorimeter (ECal) surrounding the neutrino target detector sub-systems of the near detector. It is based on layers of extruded plastic scintillator bars with Lead sheets sandwiched between them. It provides near-hermetic coverage for all particles exiting or coming into the near detector. This highly segmented system's function is to image tracks and energy deposition from particles produced in neutrino interactions. The detection of energy deposition from charged particles down to ~ 200 keV has been demonstrated with the system. Large light yield at 1 m away from the end of the bar has been achieved by threading the centres of the bars wavelength shifting fibres to collect the light produced and transport it to solid state, photon detecting devices called MPPCs. MPPCs give very good reproducibility of performance to better than 10% across the whole system and operation over long period of time (a few years) and are incredibly reliable and tough with few dead channels in the whole detector (~50 dead out of 20,000). For the project the design and calorimetric capabilities have already been proven in the T2K project, the recent earthquake in Japan (2011) is testament to the robustness of the detector. The project reuses many of the spares electronics components from T2K. For the reactor monitor detector, the ECal design has been reconfigured for anti-neutrino detection by replacing the lead with the gadolinium. The gadolinium is used to capture the neutrons produced in anti-neutrino interactions. When a neutron is captured by a gadolinium nucleus a large shower (~8 MeV) of photons it created leaving a unique signal in the detector. By correlating this unique neutron signal with an earlier positron signal we can efficiently select anti-neutrino interactions. The device has been testing in the laboratories at the University of Liverpool using various radio-active sources. In order to test the device in realistic conditions and advance the project, we propose to deploy the detector at a commercial nuclear reactor. Deployment of the detector has been negotiated with the aid of The UK Safeguards Support programme to the IAEA and the Department of Energy and Climate Control. Upon the successful outcome of the group will seek to start field tests with the IAEA. If the field tests are successful reactor monitoring detectors will be deployed at reactors around the world as part of the IAEA's efforts to ensure peaceful use of nuclear material.

在过去的6 - 7年中，STFC领导了一个学术联盟，该联盟发展了一个大型中微子检测器，这是日本国际实验的一部分，称为T2K。利物浦集团认为，为这项国际工作开发的技术可以改编成一个小的占地面积，高度可靠的检测器，以表征从操作核裂变反应堆核心发出的抗中性替代物。当与反应堆功率输出相关时，测量电站的抗内膜排放的数量和能量水平是一种非常有效的方法，是检测未宣布的未闭上关闭的方式，以及是否秘密地从过程中删除了高级核材料，这是IAEA的理想方法，用于检测探测器，用于探测the ecter the ecal the ecal the ecal the ecal the ecal the ecal inte ecal inte ecal ins t2k same t2k same t2K近检测器的中微子目标探测器子系统。它基于挤出的塑料闪烁杆层，铅片夹在它们之间。它为所有退出或进入近探测器的颗粒提供了近乎热的覆盖范围。这个高度分割的系统的功能是来自中微子相互作用中产生的颗粒的图像轨道和能量沉积。该系统已经证明了从电荷颗粒到200 keV的能量沉积的检测。通过将钢筋波长移动纤维的中心螺纹收集产生的光并将其运输到固态，光子检测到称为MPPCS的设备，可以在距离杆末端1 m的巨大产量达到。 MPPC在整个系统中提供了非常良好的性能可再现性能比10％，并且在长期（几年）中运行，并且在整个检测器中很少有死渠道（在20,000中死亡约50）。对于该项目，T2K项目已经证明了设计和量热功能，日本最近的地震（2011年）证明了检测器的稳健性。该项目重用T2K的许多备件电子组件。对于反应堆监测器检测器，通过用gadolium替换铅来重新配置ECAL设计，以重新配置抗中性抗体检测。 Gadolinium用于捕获在抗中性相互作用中产生的中子。当中子被gadolinuium核捕获时，会产生的大淋浴（〜8 meV）在检测器中产生独特的信号。通过将这种独特的中子信号与较早的正电子信号相关联，我们可以有效地选择抗神经相互作用。该设备一直在利物浦大学的实验室使用各种放射性来源进行测试。为了在现实条件下测试设备并推进项目，我们建议将检测器部署在商业核反应堆上。探测器的部署已在英国保障措施支持计划和能源和气候控制部的帮助下进行了协商。随着小组的成功结果，将寻求与IAEA进行现场测试。如果现场测试是成功的反应堆监测探测器，将在世界各地的反应堆中部署，这是IAEA确保和平使用核物质的努力的一部分。