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钨酸铅(PWO)晶体是一种综合性能非常优异的无机闪烁晶体,并且在高能物理研究领域已获得重要应用,但光输出偏低的缺点严重制约了它在非高能物理领域的应用.本文采用氟化铅作为掺杂剂,用Bridgman方法生长出了光输出比普通PWO晶体高出2—3倍的新型PWO晶体.紫外和X射线荧光光谱的测试结果表明,这种新型晶体的发光波长比纯PWO晶体红移了大约134nm,即为553nm,衰减时间也从几十纳秒延长到100ns以上,且光输出随积分时间的增加而增强.此外,发射波长和光输出沿晶体生长方向存在明显的位置依赖性,初期结晶的晶体以PWO的本征发光为主,而后期则以与氟离子有关的缺陷发光为主.
Lead tungstate (PWO) crystal is a kind of inorganic scintillation crystal with very good overall performance and has obtained important applications in the field of high-energy physics, but the disadvantage of low light output seriously restricts its application in non-high-energy physics. Using lead fluoride as dopant, a novel PWO crystal with light output 2-3 times higher than that of ordinary PWO was grown by Bridgman method.The results of UV and X-ray fluorescence spectroscopy showed that the emission wavelength of this novel crystal Which is about 134nm redder than pure PWO crystal, which is 553nm, the decay time also extends from dozens of nanoseconds to over 100ns, and the light output increases with the increase of integral time. In addition, the emission wavelength and light output are obvious along the crystal growth direction The crystal structure of the initial crystal is mainly emissive with PWO, while the latter with the fluoride ion-related defects.