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完成了６４０—１０４０℃温度范围内钨酸铅［ＰｂＷＯ４（ＰＷＯ）］晶体的退火实验，观察到较低温退火时晶体中本征色心吸收带（３５０ｎｍ）先是增加，其后随退火温度的升高而逐渐降低直至消除的全过程．分析了ＰＷＯ晶体的本征缺陷和电荷补偿机制．讨论了退火过程中氧进入晶体后色心的产生和转化规律，并提出可能发生Ｐｂ３＋→Ｐｂ４＋的进一步氧化过程，从而导致Ｐｂ３＋空穴中心的湮没．测量并比较了不同退火温度处理后ＰＷＯ晶体的紫外辐照诱导色心吸收谱．观察到导致辐照损伤的Ｏ－空穴中心主要来自晶体中固有的Ｐｂ３＋空穴中心向Ｏ－空穴中心的转化；同时晶体中氧空位作为电子陷阱对Ｏ－空穴中心有稳定作用．当上述两项因素得以消除，晶体辐照硬度随之提高．实验表明，在含氧气氛中高温退火可以有效地改进ＰＷＯ晶体的抗辐照损伤能力．铁杂质对ＰＷＯ的抗辐照能力十分有害
The annealing experiment of lead tungstate [PbWO4 (PWO)] was completed at the temperature range of 640-1040 ℃. It was observed that the intrinsic color center absorption band (350nm) of the crystal at the lower temperature annealed first increased, and then increased with the annealing temperature High and gradually reduce until the elimination of the whole process. The intrinsic defects of PWO crystals and charge compensation mechanism are analyzed. The formation and transformation of the color center after the oxygen enters the crystal are discussed. The further oxidation process of Pb3 + → Pb4 + is suggested, which leads to the annihilation of Pb3 + hole center. The color center absorption spectra of PWO crystals induced by different annealing temperatures were measured and compared. It is observed that the O-hole center leading to the irradiation damage mainly comes from the conversion of the intrinsic Pb3 + hole center in the crystal to the O-hole center; meanwhile, the oxygen vacancies in the crystal act as electron traps to stabilize the O-hole center. When the above two factors are eliminated, the hardness of the crystal radiation increases accordingly. Experiments show that high temperature annealing in an oxygen-containing atmosphere can effectively improve the PWO crystal anti-irradiation damage ability. Iron impurities on PWO anti-radiation ability is very harmful