引力波伽马射线暴探测用大尺寸溴化镧晶体封装件的制备及性能研究

Preparation and Properties of Large Size LaBr 3 Crystal Packages for Gravitational Wave Gamma-Ray Burst Detection

本文采用改进的坩埚下降法生长了∅76 mm×76 mm的以氯化铈(CeCl 3)为掺质的溴化镧(LaBr 3)晶体。该晶体经切割、研磨加工、封装制成超薄铍(Be)金属LaBr 3晶体防潮封装件,封装件的晶体尺寸为∅76 mm×15 mm,入射窗选用200μm厚的Be金属片,当入射能量为5.9 keV时能量分辨率为55%。对封装件依次开展力学(1000 g冲击、14.12 g随机振动)、热真空(-40~+50℃、≤1.3×10^(-3)Pa)、辐照(160 krad剂量60 Co辐照)试验,并对试验前后封装件进行闪烁性能表征。结果表明,试验前后晶体外观无肉眼可见变化,662 keV的能量分辨率由5.30%变至4.89%,光输出损失0.2%。

The∅76 mm×76 mm LaBr 3 crystal doped with CeCl 3 was grown by modified Bridgman technique.The crystal was cut and ground to∅76 mm×15 mm,and packed in a housing to prevent hygroscopic effects.The entrance window was comprised of a 200μm thick Be sheet.The energy resolution of package is 55%under 5.9 keV gamma-ray excitation.The scintillation performance of the package was characterized before and after mechanical test(1000 g impact and 14.12 g random vibration),thermal vacuum test(-40~+50℃,≤1.3×10^(-3)Pa),and irradiation test(160 krad dose of 60 Co irradiation).The results show that there is no change in the appearance of crystal.The energy resolution of the package changes from 5.30%to 4.89%under 662 keV gamma-ray excitation,the light output loss is 0.2%.