A new large area MCP-PMT for high energy detection.-猫眼课题宝

DOI：

10.1038/s41598-023-47818-x

发表时间：

2023-11-22

期刊：

Scientific reports

影响因子：

4.6

通讯作者：

中科院分区：

综合性期刊3区

文献类型：

作者：

来源链接：

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10665327/

20-微通道板大面积光电倍增管（MCP PMT）是我国最新研制的一种光电倍增管。它广泛应用于江门地下中微子观测站（JUNO）、中国金平地下实验室（CJPL）和大型高空空气簇射观测站（LHAASO）等高能探测实验。针对现有MCP PMT时间性能差的问题，提出了一种新的大面积MCP PMT设计方案。在CST Studio Suite中开发了三维模型，验证了其可行性。采用有限积分技术和蒙特卡罗方法，详细研究了聚焦电极尺寸、偏压和微通道板结构对收集效率和时间性能的影响。基于模拟结果，选择了优化的操作和几何参数。结果表明，平均光电子落在MCP有源区的比例为97.5%。由于当撞击MCP顶表面时发射多个二次电子，撞击光电子的接受分数接近100%。从光阴极发射的光电子的平均渡越时间扩展（TTS）为1.48 ns。

20-inch Large area photomultiplier tube based on microchannel plate (MCP-PMT) is newly developed in China. It is widely used in high energy detection experiments such as Jiangmen Underground Neutrino Observatory (JUNO), China JinPing underground Laboratory (CJPL) and Large High Altitude Air Shower Observatory (LHAASO). To overcome the poor time performance of the existing MCP-PMT, a new design of large area MCP-PMT is proposed in this paper. Three-dimensional models are developed in CST Studio Suite to validate its feasibility. Effects of the size and bias voltage of the focusing electrodes and MCP configuration on the collection efficiency (CE) and time performance are studied in detail using the finite integral technique and Monte Carlo method. Based on the simulation results, the optimized operating and geometry parameters are chosen. Results show that the mean ratio of photoelectrons landing on the MCP active area is 97.5%. The acceptance fraction of the impinging photoelectrons is close to 100% due to the emission of multiple secondary electrons when hitting the MCP top surface. The mean transit time spread (TTS) of the photoelectrons from the photocathode is 1.48 ns.