大尺寸掺氯化铈的溴化镧晶体生长及闪烁性能研究  

Study on Crystal Growth and Scintillation Properties of Large-size CeCl_3 Doped LaBr_3 Crystal

作　　者：桂强 张春生 张明荣 杭利军 方珍意 葛云程 

机构地区：[1]北京一轻研究院,北京101111

出　　处：《核电子学与探测技术》2011年第11期1195-1197,1249,共4页Nuclear Electronics & Detection Technology

摘　　要：采用真空密封的石英坩埚,使用改进的下降法生长了以氯化铈为掺质的溴化镧晶体(LaBr3:CeCl3),获得尺寸Φ40 mm×45 mm无宏观缺陷晶体。测试了LaBr3:CeCl3晶体的X射线激发发射谱、透射光谱及光输出、能量分辨率、衰减时间等闪烁性能。结果表明:在X射线激发下,Ce3+激发发光主峰位于385 nm附近,且其光透过率高达70%。在137Cs放射源作用下,LaBr3:5%CeCl3晶体的光产额可达到12 000 photoelectrons/MeV,能量分辨率高约2.9%,并且衰减时间达16.4 ns。与NaI晶体相比,LaBr3:CeCl3晶体以其优良的闪烁性能更加适用于放射性核素识别设备上。It presented the growth method and scintillation properties of large-size LaBr3 crystals.LaBr3 crystals doped with CeCl3 concentrations,i.e.LaBr3：CeCl3 crystals were grown by modified Bridgman technique from the melt of the mixtures of anhydrous lanthanum bromide and cerium chloride powders in sealed fused silica crucibles in vacuum.Their X-ray excited luminescent spectra,optical transmittance spectra,light yields,decay times and energy resolutions were measured at room temperature.The results show that the emission of 5%CeCl3 doped crystal is peaked at 385 nm under X-ray excitation and its optical transmittance at the wavelength is about 70% besides,the crystal has 2.9% energy resolution and about 12 000 photoelectrons/MeV light yield under γ-ray excitation of 137Cs radioactive source,and its decay time is about 16.4 ns.LaBr3：CeCl3 crystal has more excellent scintillation properties and is very suitable for the radio-isotope identification device.

关 键 词：溴化镧 氯化铈 Ce3+发光 稀土卤化物 闪烁晶体 

分 类 号：O78[理学—晶体学]