A 16-Channel Real-Time Digital Processor for Pulse-Shape Discrimination in Multiplicity Assay
A 16-Channel Real-Time Digital Processor for Pulse-Shape Discrimination in Multiplicity Assay
复制标题
用于多重分析中脉冲形状辨别的 16 通道实时数字处理器
DOI：
10.1109/tns.2014.2322574
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发表时间：
2013
影响因子：
1.8
通讯作者：
A. Lavietes
中科院分区：
文献类型：
--
作者：
M. Joyce;M. Aspinall;F. Cave;A. Lavietes
近年来，实时中子/γ射线脉冲形状鉴别已成为可行的，可与基于闪烁器的探测器一起使用，这些探测器的响应速度极快，脉冲宽度为25 ns，并且已报告了它们在各种核材料分析中的应用。对于核材料的现场分析，测量通常基于自发裂变事件的多重性评估。这方面的一个例子是240 P ueff评估源于长期建立的技术开发的3 He为基础的中子符合计数器时，3 He丰富和便宜。然而，如果使用中的探测器的数量类似地限于3或4，则当使用闪烁体探测器时，这种测量可能受到低探测效率和低符合阶数（通常限于三倍）的困扰。相反，被布置成优化效率和多重性灵敏度的> 10个检测器模块的阵列将性能要求方面的重点转移到实时数字分析仪，并且关键地转移到这些系统中固件的时间处理窗口中剩余的范围。在本文中，我们报告的设计，开发和调试的定制，16通道实时脉冲形状歧视分析仪指定的材料分析的挑战，上面总结。该分析仪集成了16个专用和独立的高压电源沿着，以及16个独立的数字处理通道，以每秒3 × 106个事件的速率提供脉冲形状鉴别。这些功能通过专用的图形用户界面进行配置，所有设置都可以即时调整，分析仪仅有效配置一次（如需要），用于随后的即插即用连接，例如连接到燃料棒束有机闪烁探测器阵列。
In recent years, real-time neutron/γ -ray pulse-shape discrimination has become feasible for use with scintillator-based detectors that respond extremely quickly, on the order of 25 ns in terms of pulse width, and their application to a variety of nuclear material assays has been reported. For the in-situ analysis of nuclear materials, measurements are often based on the multiplicity assessment of spontaneous fission events. An example of this is the 240P ueff assessment stemming from long-established techniques developed for 3He-based neutron coincidence counters when was 3He abundant and cheap. However, such measurements when using scintillator detectors can be plagued by low detection efficiencies and low orders of coincidence (often limited to triples) if the number of detectors in use is similarly limited to 3 or 4. Conversely, an array of > 10 detector modules arranged to optimize efficiency and multiplicity sensitivity, shifts the emphasis in terms of performance requirement to the real-time digital analyzer and, critically, to the scope remaining in the temporal processing window of the firmware in these systems. In this paper we report on the design, development and commissioning of a custom-built, 16-channel real-time pulse-shape discrimination analyzer specified for the materials assay challenge summarized above. The analyzer incorporates 16 dedicated and independent high-voltage supplies along with 16 independent digital processing channels offering pulse-shape discrimination at a rate of 3 × 106 events per second. These functions are configured from a dedicated graphical user interface, and all settings can be adjusted on-the-fly with the analyzer effectively configured one-time-only (where desired) for subsequent plug-and-play connection, for example to a fuel bundle organic scintillation detector array.