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通过正电子湮没寿命谱研究了PbWO_4晶体退火处理前后缺陷的变化；发现氧退火后，晶体正电子寿命值τ_2变小，正电子捕获率κ增大，真空退火反之。并且PbWO_4晶体氧退火后发光主峰位从440nm移到485nm的绿光处，而真空退火晶体发射谱谱形并未变化。从不同退火处理对晶体的影响，提出了PbWO_4晶体中铅空位形成WO_3＋O~-发绿光的发光模型。
The positron annihilation lifetime spectrum was used to investigate the changes of the defects before and after the annealing of PbWO_4 crystal. After the oxygen annealing, the positron lifetime value τ_2 of the PbWO_4 crystal decreases and the positron trapping rate κ increases. And the main peak of luminescence of PbWO_4 crystal annealed from 440nm to the green of 485nm after the oxygen annealing of PbWO_4 crystal, the shape of the vacuum annealing crystal did not change. Based on the influence of different anneal treatments on the crystal, a luminescence model of lead vacancies in WO_3 + O ~ - green light was proposed for PbWO_4 crystal.