【作者】 朱鹏；

【导师】 刘义保；

【作者基本信息】 东华理工大学 ， 核能与核技术工程， 2012， 硕士

【摘要】 为了确保不发生核扩散，在恐怖行动越来越多的今天，核材料的监视与测试技术正变得越来越重要。利用宇宙射线μ子对高z物质进行成像的技术是一种新型的重核物质检测技术。利用宇宙线μ子作为粒子射线源，采用新型高位置分辨阻性板室（Resistive Plate Chamber，简称RPC）作为μ子径迹探测器，成功研制了可实现宇宙线高z物质成像的系统。作为这个探测器系统中的关键部分，阻性板室这种气体探测器，需要大力研究以提高其位置灵敏度。多气隙阻性板室（Multi-gap Resistive Plate Chamber，简称MRPC）拥有良好的效率和时间分辨特性。在效率超过90%的情况下，已经获得了时间分辨率为60ps的实验结果。最近的研究表明MRPC在一维或二维位置分辨上可能具有良好的性能。此前众多实验已经证明，RPC在时间分辨和一维空间分辨上表现良好。尽管在理论上存在某些困难，但是用于二维位置分辨的RPC已经在印度进行过成功的实验。我们研究小组设计和组装了具有二维读出结构的MRPC原型探测器。基于来自宇宙射线的μ子的测试实验也已进行，我们使用光电倍增管（PMT）信号符合系统来进行触发。表征空间分辨率的相关参数的分析结果表明，MRPC能被用作二维位置探测器，只要设计好合适的信号地以及读出电路，以压制噪声和信号反射。在某些情况下，信号传输比信号产生对探测器的性能的影响更为关键。我们也测试了一些MRPC式和RPC式的一维位置探测器。我们发现，MRPC在一维空间分辨率方面的性能比RPC更好，它的信噪比更高。好于100μm的位置分辨率已经在实验中获得。同时实验结果也清晰地显示出二维读出结构会对信号质量和信噪比产生严重的不利影响，而这方面的研究会成为以后位置灵敏探测器工作的焦点。更多还原

【Abstract】 In order to ensure nuclear non-proliferation, nuclear materials monitoring andtesting technology is becoming more important with the fact of more and moreterrorist actions. Radiography of high z material with muon from cosmic ray is anovel technology for heavy nuclear material detection. Using cosmic ray muon asparticle source and a resistive plate chamber with high position resolution as muontracking detector, a testing system is successfully developed to realize high z materialradiography with cosmic ray. As key part of the detector system, resistive platechamber, a kind of gaseous detector, is need to study and improve position sensitivity.The MRPC, multi-gap resistive plate chamber, has very good efficiency and timeresolution. An experimental result of60ps with over90%efficiency has beenobtained. Recent Study demonstrates that there is high probability of good positionresolution in one dimension or two dimensions for MRPC. The RPC has a goodperformance in time and spatial resolution in one dimension, which has beenconfirmed in many experiments. In spite of some difficulties of theory, successfulexperiment has been carried on in India for RPC used as two-dimension positiondetector.A prototype of MRPC with two-dimension readout has been designed andassembled in our group. Experiments based on muon from cosmic rays have beencarried on, which use PMT signal coincidence system as trigger. The analysis resultof some parameters related to spatial resolution indicates that MRPC can be used astwo-dimension position detector so long as suitable signal ground and readout circuit have been designed to suppress noise and reflection. In some cases, the signaltransmission is more crucial than the signal generation.We also test some MRPC-style and RPC-style one-dimension detectors. We findMRPC has better performance than RPC on one-dimension spatial resolution and thesignal-to-noise ratio is very high. A result of better than100μm spatial resolution hasbeen obtained. And the experiment results clearly show that two-dimension readoutstructure causes serious adverse influence for signal quality and signal-to-noise ratio,becoming the focus of study on position sensitive detector.更多还原