On the response of GdAlO3:Ce powder scintillators

作者:Michail C*; Kalyvas N; Valais I; David S; Seferis I; Toutountzis A; Karabotsos A; Liaparinos P; Fountos G; Kandarakis I
来源:Journal of Luminescence, 2013, 144: 45-52.
DOI:10.1016/j.jlumin.2013.06.041

摘要

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/cm(2), 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.

  • 出版日期2013-12

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