基于涂硼多丝室的弧形位置灵敏中子探测器研究

Because of the shortage crisis of helium-3, alternatives to helium-3 based neutron detectors were widely developed all over the world this years. To meet the requirement of neutron diffractometer for large area curved position sensitive neutron detectors, a new position sensitive neutron detector based on B-10 films will be studied in this project. MWPCs using multilayer B-10 films as neutron converters will be employed as the detection unit, so as to realize large solid angle coverage and high thermal neutron detection efficiency of the detector. The cell structure of MWPC, the thickness and number of B-10 films will be first optimized by Monte Carlo simulation. Then, through the detector prototype fabrication and performance test, the large area boron film manufacturing processes, the wire fixed technique, and the signal readout methods will be carefully studied. Through the research of this project, techniques for the development of high efficiency large area curved two-dimensional position sensitive neutron detectors will be obtained. As the application of neutron diffractions in China keep increasing，the research of this project will have the practical significance to meet the needs of neutron diffraction of high precision, large solid angle neutron detectors.

在全球氦-3资源短缺的背景下，世界各国都在积极探寻替代氦-3的中子探测技术。本项目围绕中子衍射仪对大面积弧形位置灵敏中子探测器的典型需求，开展基于B-10涂层的新型位置灵敏中子探测器研究。项目拟将多丝正比室技术与多层B-10薄膜工艺结合起来，用以解决氦-3替代中子探测器在实现大覆盖立体角及高探测效率方面存在的技术难题。项目将通过蒙卡模拟，对多丝正比室单元结构、涂硼中子转换层的厚度及层数等对探测器位置分辨率、中子探测效率等的影响规律进行深入研究。在此基础上，通过探测器原型制作和性能测试，掌握大面积涂硼中子转换层制作、弧形探测器丝层固定、信号引出与多路电子学读出等探测器制作中的关键工艺与技术。通过本项目的研究，可为大面积涂硼弧形二维位置灵敏探测器的研制与应用奠定技术基础。在我国中子衍射应用需求日益增多的情况下，本项目的研究对满足中子衍射仪对高精度、大立体角中子探测器的需求将具有实际意义。

本项目围绕中子衍射仪对大面积弧形位置灵敏中子探测器的典型需求，开展了基于B-10涂层的新型位置灵敏中子探测器研究。首先利用MC模拟, 对不同10B薄膜厚度和层数对探测器中子探测效率的影响规律进行了深入研究; 研究了不同MWPC结构参数和工作气体条件下, 探测器的位置分辨能力和中子信号响应。在此基础上，通过探测器室体的制作，掌握了涂硼薄膜的固定与定位、信号和高压引出等探测器制作的关键技术，完成了一个基于涂硼多丝室的位置灵敏中子探测器原型样机的研制。为基于涂硼丝室的中子探测器的进一步应用推广奠定了技术基础。 目前依托该项目发表学术论文4篇，在国内学术会议开展口头报告2人次，培养硕士研究生2名。