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近２０多年以来，βＰｂＦ２晶体一直是作为Ｃｈｅｒｅｎｋｏｖ辐射材料而深受实验高能物理学界的重视。随着新一代电磁量能器对闪烁晶体性能要求的不断提高，人们希望它在未来能够成为优质的闪烁晶体候选者。但纯的βＰｂＦ２晶体的发光性能仅存在于液氦温度下，当温度上升到室温时则完全猝灭。本文采用脱氧剂非真空环境下的Ｂｒｉｄｇｍａｎ法生长出了掺Ｔｂ的βＰｂＦ２晶体，并在室温下分别测试了该晶体的透射光谱、Ｘ射线激发光谱和紫外荧光光谱。结果表明，βＰｂＦ２：Ｔｂ晶体的吸收边为２４５ｎｍ，具有很宽的透光范围，透光率最高可达７５％。在Ｘ射线激发下，观察到八个强弱不等、多呈带状分布的发光峰，具有典型的分立发光中心特征。它们分别对应于Ｔｂ３＋离子不同能级之间的能级跃迁，见下表。ＴｒａｎｓｉｔｉｏｎＷａｖｅｌｅｎｇｔｈＷａｖｅｎｕｍｂｅｒＨａｌｆｗｉｄｔｈＲｅｌａｔｉｖｅ（ｎｍ）（ｃｍ－１）（ｎｍ）ｉｎｔｅｎｓｉｔｙ（％）５Ｄ３→７Ｆ６３８０．２２６１７８９．１９５５Ｄ３→７Ｆ５４１５．９２４０４４９．７３８５Ｄ３→７Ｆ４４３８．５２２８０５９．２５０５Ｄ３→７Ｆ３４６０．０２１７３９７５Ｄ３→７Ｆ２４７１．３２１２１８９５Ｄ４?
Nearly 20 years, β PbF2 crystal has been as Cherenkov radiation material and highly experimental high-energy physics community attention. With the new generation of electromagnetic energy meters for the performance requirements of scintillation crystals, it is hoped that it will become a good candidate for scintillation crystals in the future. But pure β PbF2 crystal luminescence properties exist only in the liquid helium temperature, when the temperature rises to room temperature, then completely quenched. In this paper, Tb-doped βPbF2 crystals were grown by Bridgman method under a non-vacuum environment using deoxidizer. The transmission spectra, X-ray excitation spectra and UV fluorescence spectra were measured at room temperature. The results show that, βPbF2: Tb absorption edge of the crystal is 245nm, with a wide range of light transmission, light transmission up to 75%. Under the excitation of X-ray, eight bands with different intensities and bands were observed, which showed typical bands of discrete luminescence. They correspond to the energy level transitions between different energy levels of Tb3 + ions, respectively, as shown in the following table. TransitionWavelengthWavenumberHalf-widthRelative (nm) (cm-1) (nm) intensity (%) 5D3 → 7F6380.2261789.1955D3 → 7F5415.9240449.7385D3 → 7F4438.5228059.2505D3 → 7F3460.02173975D3 → 7F2471.32121895D4?