关键词: Cs₂BaBr₄∶1%Ce³⁺晶体, 坩埚下降法, 光致发光, X射线激发发光, 衰减时间, 吸湿性

Abstract: Using BaBr₂, CsBr, and CeBr₃ with high-purity as raw materials, the Cs₂BaBr₄∶1%Ce³⁺ polycrystalline powders were synthesized by solid-state reaction method. The crystal of Cs₂BaBr₄∶1%Ce³⁺ was grown by Bridgman method. The wafer of Cs₂BaBr₄∶1%Ce³⁺ with different thickness were obtained by incising, grinding and polishing process. The phase of the crystal was analyzed, and XRD patterns show that the crystal is a uniformly molten substance with no phase transition. The scintillation performance of the crystal was studied, which the optical transmittance, photo luminescence, X-ray induced luminescence, multi-channel gamma energy spectrum and decay time were measured. Compared with the crystal of LaBr₃, the hygroscopicity of the crystal was analyzed. The results show that the optical transmittance of crystal is close to 80%, and under the excitation of ultraviolet light and X-rays in a certain band, the crystal exhibits emission peaks at wavelengths around 349 and 372 nm. The energy resolution under the excitation of gamma rays of ¹³⁷Cs is estimated to be 11%. The decay time under the excitation of UV light is fitted to be 21.9 ns. The hygroscopicity of the crystal is much better than that of LaBr₃ crystal.

Key words: Cs₂BaBr₄∶1% Ce³⁺ crystal, Bridgman method, photo luminescence, X-ray induced luminescence, decay time, hygroscopicit