X-ray Luminescence Efficiency of GAGG:Ce Single Crystal Scintillators for use in Tomographic Medical Imaging Systems

[摘要] The purpose of the present study was to evaluate different scintillator crystal samples, with a cross section of 3×3mm2and various thicknesses ranging from 4mm up to 20mm, of the new mixed Gd3Al2Ga3O12:Ce (GAGG:Ce) scintillator material under X-ray irradiation, for potential applications in Tomographic Medical Imaging systems. Evaluation was performed by determining the X-ray luminescence efficiency (XLE) (emitted light energy flux over incident X-ray energy flux) in energies employed in general X-ray imaging. For the luminescence efficiency measurements, the scintillator samples were exposed to X-rays using a BMI General Medical Merate tube, with rotating Tungsten anode and inherent filtration equivalent to 2 mm Al. X-ray tube voltages between 50 to 130 kV were selected. An additional 20 mm filtration was introduced to the beam to simulate beam quality alternation equivalent to a human body. The emitted light energy flux measurements were performed using an experimental set up comprising a light integration sphere coupled to an EMI 9798B photomultiplier tube which was connected to a Cary 401 vibrating reed electrometer. The GAGG:Ce sample with dimensions 3×3×10 mm3exhibited higher XLE values, in the whole X- ray energy range examined. XLE value equal to 0.013 was recorded for this crystal at 130 kVp - a setting frequently used in Computed Tomography applications.

[发布机构] Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, Department of Biomedical Engineering, Technological Educational Institute of Athens, Egaleo, Athens; 122 10, Greece^1

[效力级别] 医药卫生 [学科分类] 卫生学

[关键词] Crystal scintillators;Luminescence efficiencies;Photo multiplier tube;Scintillator crystals;Scintillator materials;Tomography applications;Vibrating reed electrometer;X-ray tube voltages