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arXiv · 2209.08441

Design of the PMT underwater cascade implosion protection system for JUNO

Miao He·Zhonghua Qin·Shaojing Hou·Xiaoping Jing·Hongbang Liu·Zunjian Ke·Diru Wu·Wan Xie·Mehang Xu·Fang Chen·Junguang Lu·Yuekun Heng·Jiawen Zhang·Xiaoyan Ma·Zhipeng Du
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Abstract

Photomultiplier tubes (PMTs) are widely used underwater in large-scale neutrino experiments. As a hollow glass spherelike structure, implosion is unavoidable during long-term operation under large water pressure. There is a possibility of cascade implosion to neighbor PMTs due to shockwave. Jiangmen Underground Neutrino Observatory designed a protection structure for each 20-inch PMT, consisting of a top cover, a bottom cover, and their connection. This paper introduces the requirement and design of the PMT protection system, including the material selection, investigation of manufacture technology, and prototyping. Optimization and validation by simulation and underwater experiments are also presented.

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Miao He, Zhonghua Qin, Shaojing Hou, Xiaoping Jing, Hongbang Liu, Zunjian Ke, Diru Wu, Wan Xie, Mehang Xu, Fang Chen, Junguang Lu, Yuekun Heng, Jiawen Zhang, Xiaoyan Ma, Zhipeng Du. 2022-09-18. Design of the PMT underwater cascade implosion protection system for JUNO. https://doi.org/10.1088/1748-0221/18/02/p02013

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