溴(氟)化镧(铈)晶体生长与性能研究  

Growth and Scintillation Properties of CeF_3-doped LaBr_3 Crystal

作　　者：桂强 张春生 邹本飞 张明荣 

机构地区：[1]北京一轻研究院,北京101111

出　　处：《人工晶体学报》2013年第4期639-642,共4页Journal of Synthetic Crystals

基　　金：北京市优秀人才项目资助

摘　　要：本文使用改进的Bridgman下降法定向生长出了直径1.5英寸的溴(氟)化镧(铈)晶体,即掺氟化铈的溴化镧晶体(简称LBF),测试了样品的耐湿性、X射线激发发射光谱以及光输出、能量分辨率、衰减时间特性等闪烁性能指标,并与掺氯化铈、溴化铈等掺质的溴化镧晶体(简称为LBC、LB晶体)进行对比。结果表明在水含量50 ppm条件下,LBF晶体未出现失透,其耐湿性比LBC、LB晶体有了明显的改善。在X射线激发下,LBF晶体发光主峰位于385 nm。在137Cs放射源作用下,LBF晶体能量分辨率为3.1%,衰减时间为25.1 ns,光输出相当于LB晶体的101%。LBF闪烁性能与溴化镧(铈)晶体相当,且耐湿性更强。CeF3-doped LaBr3 crystals （LBF） with a diameter of 1.5 inches were grown by a modified Bridgman technique from the melt of powders in vacuum-sealed fused crucibles. The waterlogging tolerance, X-ray excitation spectrum, light yield, decay time and energy resolution of LBF samples were measured at room temperature. The key properties of the LBF samples such as waterlogging tolerance, energy resolution, light yield, and decay time were compared with those of LBC and LB crystals. At a moisture concentration of 50 ppm, LBF crystals had no devitrification. The hygroscopic capacity was obviously lower than that of LBC and LB crystals. The wet fastness of LBF crystals was significantly improved. The emission peak of LBF crystal was at 385 nm under X-ray excitation, and it had excellent scintillation properties with the energy resolution of 3.1% under γ-ray excitation of ^Cs 37radioactive source. The decay time was 25.1 ns, and the light yield was about 101% of LB. The results indicated that LBF crystal had slightly better scintillation properties than LB did, and had a more excellent waterlogging tolerance.

关 键 词：闪烁晶体 溴化镧 氟化铈 Ce3+发光 稀土卤化物 

分 类 号：O78[理学—晶体学]