国产LaBr3：Ce晶体性能表征

摘要

作为近年来发展起来的新晶体，LaBr3：Ce有着很高的发光产额（~60000p/MeV）和较快的发光衰减时间常数（~16ns），因而成为研究热点。国内对LaBr3：Ce晶体的研究还不多，仅少数几家单位具备研究生产条件。本工作采用北京华凯龙电子有限公司生产的LaBr3：Ce晶体（晶体尺寸为椎30mm×20mm），配合XP20D0光电倍增管，采用单光电子方法测量得到其光电子产额为16800p.e/MeV；并测量了其发光衰减曲线，计算得到上升时间为5.6ns，发光衰减时间常数为21ns；其对137Cs的能量分辨率为3.3%。采用两块椎30mm×20mm的LaBr3：Ce晶体与两只XP20D0光电倍增管，测量得到对2 Na的符合时间分辨率为191ps；这些表征为国产LaBr3：Ce晶体的酌谱仪研究工作提供了重要参考。%LaBr3:Ce is a new scintillator crystal, which draws lots of interest recently due to its high light yield (~60000p/MeV) and short decay time constant (~16ns). In this work, theФ30mmí20mmLaBr3:Ce scintillator produced by Beijing Huakailong electronics Co. Ltd.was used to couple to a XP20D0 PMT. The light yield and the light decay curve were measured by the photon-electronmethod. The light yield is 16800p.e/MeV and the decay constant is 21ns, respectively. The energy resolution for 137Cs source is 3.3%. Two bulks of Ф30mmí20mmLaBr3:Ce scintillator crystal and two XP20D0 PMTs were deployed to assemble a time spectrometer. The time resolution FHWM=191ps was got for 22Na source. This report on characterizationof the domesticLaBr3:Ce scintillator crystal could be useful for studying gamma spectrometers.