On the response of GdAlO₃:Ce powder scintillators

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• 作者：C. Michail ; N. Kalyvas ; I. Valais ; S. David ; I. Seferis ; A. Toutountzis ; A. Karabotsos ; P. Liaparinos ; G. Fountos ; I. K ; arakis
• 关键词：Inorganic scintillators ; Radiation detectors ; GdAlO3 ; Ce
• 刊名：Journal of Luminescence
• 出版年：2013
• 出版时间：December, 2013
• 年：2013
• 卷：144
• 期：Complete
• 页码：45-52
• 全文大小：1962 K

文摘

The aim of the present study was to investigate the luminescence efficiency (XLE) of gadolinium aluminum perovskite (GdAlO₃:Ce) powder scintillator. This powder phosphor, also known as GAP:Ce scintillator, is a non-hygroscopic material, emitting blue light with short decay time. For the purposes of this study, five scintillating screens with coating thicknesses, 14.7, 31.0, 53.7, 67.2 and 121.1 mg/cm², were prepared in our laboratory from GdAlO₃:Ce powder (Phosphor Technology, Ltd) by sedimentation on silica substrates. The light emitted by the phosphors under investigation was evaluated by performing measurements of the absolute luminescence efficiency (AE), X-ray luminescence efficiency and detector quantum gain (DQG) under X-ray exposure conditions with tube voltages ranging from 50 to 140 kV. The quantum detection efficiency (QDE) and energy absorption efficiency (EAE) were also evaluated. The spectral compatibility of GdAlO₃:Ce, with various existing optical detectors, was investigated after emission spectra measurements. A theoretical model, describing radiation and light transfer, was used to fit experimental AE data. This has allowed the estimation of optical attenuation coefficients of the scintillator. GdAlO₃:Ce exhibited higher QDE and EAE values, compared to aluminium perovskite (YAlO₃:Ce) but lower absolute efficiency values. Absolute efficiency was found to increase with increasing X-ray tube voltage, although for values higher than 120 kVp a decrease was observed.