Using a LaBr_3:Ce scintillator for positron annihilation lifetime spectroscopy  

作　　者：刘军辉 李道武 章志明 王宝义 张天保 郝佳 魏龙 

机构地区：[1]Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences [2]Beijing Engineering Research Center of Radiographic Techniques and Equipment [3]Number 8, Qinghe Building [4]Beijing Huakailong Electronics Co.Ltd

出　　处：《Chinese Physics C》2012年第4期380-383,共4页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China(10805049,10775149)

摘　　要：A LaBr3：Ce scintillator has a high light output （～60000 p.e/MeV） and a short decay constant （25 ns）, which makes it good for time spectrometry. Compared with a BaF2 scintillator, it can bear a much higher count rate, and can be coupled to photomultipliers without using a quartz window. In this work, a positron annihilation lifetime spectrometer （PALS） consisting of two bulks of φ25 mm×25 mm LaBr3：Ce scin- tillator coupled to two XP20D0 photomultipliers, respectively, was built. A time resolution of FWHM=206 ps was measured for the PALS with a 60Co source at the energy window for 22Na. With this spectrometer, a reasonable lifetime value τ =221±4 ps in a pure Si sample is obtained, which means that the utilization of LaBr3：Ce as the detector for a PALS is feasible.A LaBr3：Ce scintillator has a high light output （～60000 p.e/MeV） and a short decay constant （25 ns）, which makes it good for time spectrometry. Compared with a BaF2 scintillator, it can bear a much higher count rate, and can be coupled to photomultipliers without using a quartz window. In this work, a positron annihilation lifetime spectrometer （PALS） consisting of two bulks of φ25 mm×25 mm LaBr3：Ce scin- tillator coupled to two XP20D0 photomultipliers, respectively, was built. A time resolution of FWHM=206 ps was measured for the PALS with a 60Co source at the energy window for 22Na. With this spectrometer, a reasonable lifetime value τ =221±4 ps in a pure Si sample is obtained, which means that the utilization of LaBr3：Ce as the detector for a PALS is feasible.

关 键 词：PALS LaBr3：Ce 

分 类 号：TL812[核科学技术—核技术及应用]