PMT光阴极均匀性对液闪衰减长度测量影响的研究

Research About the Effects of PMT Photocathode Uniformity on the Measurement of Attenuation Length of LS

江门中微子实验是测定中微子的质量顺序和精确测量中微子混合参数的实验,中心探测器直径为35.4 m,探测器内液体闪烁体的衰减长度至少为20 m。在液闪研制过程中需实时监测衰减长度的变化,液闪衰减长度的精确的测量成为液闪研制的一个重要课题。本文研究了测量系统中PMT中心位置附近光阴极的均匀性,对比了不同均匀性的PMT在系统中时衰减长度测量结果,得出了PMT光阴极均匀性对测量系统的影响,为提高系统测量的稳定性和精度提供了依据。

JUNO （Jiangmen Underground Neutrino Observatory） is an experiment that designed to determine neutrino mass hierarchy and precisely measure oscillation parametem. ？ The diameter of center detector in JU- NO is 35.4 meter. Therefore, it has a high request that the attenuation length of LS is larger than 20 meter. In the course of the development of LS, it requires continuing and measuring the attenuation length in real time. The accurate measurement of attenuation length of LS becomes extremely important. In this study we measured the photocathede response of the PMT and compared different results when the PMT of the system is different. This study displayed that PMT photocathode uniformity really has an effect on the measurement of attenuation length of LS and gives a basis for the reliability of the system.