Characterization of 3-inch photomultiplier tubes for the JUNO central detector

• DOI: 10.1007/s41605-018-0085-8
• Publication Date: 2018-11-22T15:18:47Z
• Authors: Nan Li; Yue-kun Heng; Miao He; Ji-lei Xu; Xuan-tong Zhang; Chuan-ya Cao; Zhi Wu; Feng-jiao Luo; Zhi-min Wang; Xiao-yu Yang; Mei-hang Xu; Zhong-hua Qin; Yu-zhen Yang; Bao-jun Yan; Shu-lin Liu
• Keywords: Characterization

Jiangmen Underground Neutrino Observation (JUNO) is one of the largest experimental facilities for neutrino detecting. As its main structure, the central detector contains 20 kiloton liquid scintillator filled in an acrylic shell, and there are 18,000 20-inch photomultiplier tubes (PMTs) and 25,000 3-inch PMTs covering the shell. As an independent photon detection system, 3-inch PMTs have been required to have excellent resolution for the single photoelectron detection, high quantum efficiency, small transit time spread and low dark noise rate. Two kinds of 3-inch PMTs from HZC Photonics and Hamamatsu have been investigated as candidates. A dedicated test system for 3-inch PMTs has been designed, and various characterization parameters have been studied. The preliminary results show these PMTs can meet the requirements of JUNO.