Scintillation Characteristics of the Single-Crystalline Film and Composite Film-Crystal Scintillators Based on the Ce3+-Doped (Lu,Gd)3(Ga,Al)5O12 Mixed Garnets under Alpha and Beta Par-ticles, and Gamma Ray Excitations

The crystals of (Lu,Gd)3(Ga,Al)5O12 multicomponent garnets with high density ρ and effective atomic number Zeff are characterized by high scintillation efficiency and a light yield value up to 50,000 ph/MeV. During recent years, single-crystalline films and composite film/crystal scintillators were developed on the basis of these multicomponent garnets. These film/crystal composites are potentially applicable for particle identification by pulse shape discrimination due to the fact that α-particles excite only the film response, γ-radiation excites only the substrate response, and β-particles excite both to some extent. Here, we present new results regarding scintillating properties of selected (Lu,Gd)3(Ga,Al)5O12:Ce single-crystalline films under excitation by alpha and beta particles and gamma ray photons. We conclude that some of studied compositions are indeed suitable for testing in the proposed application, most notably Lu1.5Gd1.5Al3Ga2O12:Ce film on the GAGG:Ce substrate, exhibiting an α-particle-excited light yield of 1790–2720 ph/MeV and significantly different decay curves excited by α- and γ-radiation.

具有高密度ρ与有效原子序数Zeff的(Lu,Gd)3(Ga,Al)5O12多组分石榴石晶体，具备优异的闪烁效率，光产额最高可达50000光子/兆电子伏特（ph/MeV）。近年来，基于此类多组分石榴石体系，研究者已开发出单晶薄膜与薄膜/晶体复合闪烁体。鉴于α粒子仅激发薄膜响应、γ辐射仅激发衬底响应，而β粒子可在一定程度上同时激发二者，此类薄膜/晶体复合材料可通过脉冲形状甄别实现粒子识别，具备潜在应用前景。本文报道了选定的(Lu,Gd)3(Ga,Al)5O12:Ce单晶薄膜在α粒子、β粒子与γ射线光子激发下的闪烁性能最新研究成果。经研究表明，部分受试组分确实适用于上述拟议应用场景的测试，其中尤以生长于GAGG:Ce衬底上的Lu1.5Gd1.5Al3Ga2O12:Ce薄膜最为突出：该薄膜在α粒子激发下的光产额为1790~2720光子/兆电子伏特，且α与γ辐射激发的衰减曲线存在显著差异。