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,为此需要建造一个直径约34.5 m的球形液体闪烁体探测器.为了保证在闪烁体中产生的光子可以传输到球面上布置的光电倍增管而不被自身吸收,这就对液体闪烁体的衰减长度及其测量方法提出了很高的要求.本项目经过对算法、相机本底等方面的研究,实现了用CMOS相机取代光电倍增管测量衰减长度,并且重新搭建结构和编写程序.最终精简了整个系统,使调试更加方便,在保证测量准确度的前提下实现全自动测量,在节省时间和人力的同时,也减少了误差.
The Jiangmen Underground Neutrino Observatory (JUNO) is an experiment designed to measure mass hierarchy and oscillation parameters. To achieve that, a sphere scintillation detector with diameter 34.5 m is to be built. To ensure the scintillation light produced by liquid scintillator can travel through the whole detector and be detected by surrounding PMTs, it is important to increase the attenuation length and find an effective way to measure it. By studying the algorithm and background noise, PMT is replaced by CMOS camera. System's structure is rebuilt and the measurement software is developed. Those simplify the whole system, and makes system more easily to be adjusted. The measuring system can wore automatically without compromise for measurement accuracy. Meanwhile, manpower is saved and error caused by human operation is reduced.