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Gadolinium pyrosilicate (GPS, Gd2Si2O7) single crystals with different doping concentrations of Tb (0.1–2.0 mol%) are successfully fabricated using the floating-zone technique. In this work, the dependence of Tb-doping concentration on the photoluminescence (PL) and scintillation properties of Tb-doped GPS (Tb:GPS) has been investigated. The PL emission contour graph shows multiple emissions, with the strongest emissions at 378 nm for 0.1% and 0.5% Tb-doping and 544 nm for 1.0% and 2.0% Tb-doping, corresponding to Tb3+ 4f-4f transitions. The PL lifetimes of the specimens range from 4.89 to 5.22 ms. The scintillation spectra exhibit comparable wavelength and intensity trends to the PL emission. The scintillation lifetimes of the specimens range from 2.41 to 3.88 ms. The Tb:GPS specimens demonstrate a relatively excessive afterglow level, with Af20 values ranging from 1640 to 7250 ppm and Af40 values ranging from 136 to 362 ppm. Using recently developed pulse height measurement for millisecond decay scintillators, under excitation at 662 keV γ-rays, the 1.0% Tb:GPS specimen exhibits the highest scintillation light yield among all other specimens at 95,600 ph/MeV, making Tb:GPS one of the highest light yield oxide scintillators. [ABSTRACT FROM AUTHOR]

Tm-doped Y3Al5O12 (YAG) single crystals with different Tm concentrations (0.1, 0.5, 1.0, and 2.0%) were grown using the floating zone method. X-ray-induced scintillation spectra, scintillation decay curves, and γ-ray-induced pulse height spectra of the obtained Tm-doped YAG single crystals were investigated. All the samples showed emission peaks due to the 4f-4f transitions of Tm3+ ions, and the decay times were around 40-20 µs under X-ray excitation. The 0.5% Tm-doped YAG sample showed the highest light yield under 662 keV γ-ray excitation among the samples. The optimal dopant concentration of Tm-doped YAG single crystals was confirmed to be 0.5%. [ABSTRACT FROM AUTHOR]

Pr-doped (Lu1− x , Y x )2Si2O7 (x = 0.25, 0.5, and 0.75) crystals were synthesized by the floating zone method. Emission peaks due to 5d–4f transitions of Pr3+ were observed at 300 nm under excitation of both UV light and X-rays. Scintillation decay times of 19–22 ns were obtained, and they originated from the 5d–4f transitions of Pr3+. Afterglow levels became high from 64.7 to 541 ppm as the Y-admixed concentration increased. The light yields were estimated to be 560–700 photons MeV−1 by comparing the channels of photoabsorption peaks from the pulse height spectra of 137Cs γ -rays measured using prepared crystals and commercial Gd2SiO5 reference. [ABSTRACT FROM AUTHOR]

In this study, we successfully made Ag2O–Cs2O–MgO–Al2O3–P2O5 glasses with different Ag concentrations (0, 0.1, 0.3, 1.0, and 3.0 mol.%) by the melt-quenching method. We measured photoluminescence (PL) properties, the radio-photoluminescence (RPL) phenomenon, and spatial resolution on the X-ray imaging to check the capability of RPL imaging plate. RPL was observed in the Ag-doped samples by irradiating X-rays, and the new emission appeared at around 620 nm. According to the shape of the PL spectrum and lifetime, the emission was confirmed to be due to Ag2+ with lifetimes of 14.0–15.9 ns. In the X-ray imaging resolution test, the 3.0% Ag-doped sample had a spatial resolution of at least 10.0 LP/mm. [ABSTRACT FROM AUTHOR]

CaSiO3 crystals doped with 0.5%, 1.0% and 2.0% Ce were developed using the floating zone method, and the scintillation and thermally-stimulated luminescence (TSL) properties were evaluated. Under X-ray irradiation, the emission peaks due to the 5dâ€"4f transitions of Ce3+ appeared at 360 nm in all the samples. Under 241Am 5.5 MeV α -ray irradiation, a clear full-energy peak appeared in all the samples, and the light yield of the 2.0% Ce doped-sample was 1040 ph/5.5 MeV- α. As a TSL dosimeter, the samples were very sensitive to X-rays and showed a good linear response from 0.1 to 1000 mGy, which was equivalent to the measurable sensitivity of commercial dosimeters for personal dose monitoring. [ABSTRACT FROM AUTHOR]

We developed SrSiO3:Ce crystals with different dopant concentrations of 0.5%, 1.0% and 2.0% using the floating zone method and investigated the scintillation and storage luminescence properties. Under X-ray irradiation, a broad emission band peaking at around 360 nm was observed in all the samples. The decay time constants were in the range of 33–34 ns, which were typical values for the 5d–4f transitions of Ce3+. The 1.0% and 2.0% Ce-doped samples showed a photoabsorption peak under 241Am 59.5 keV γ-rays and the light yield was 1200 and 1400 ph MeV−1, respectively. The results of pulse-height spectra and thermally-stimulated luminescence showed a complementary relationship between scintillation and ionizing-radiation-induced storage luminescence properties in Ce-doped SrSiO3. [ABSTRACT FROM AUTHOR]

Oxyfluoride‐based sodium‐aluminum‐phosphate glasses with a fixed 7 mol% content of Gd2O3 and various amounts of CeF3 were fabricated by the melt quenching process. The fabricated glasses (NAPGCe) were studied by physical, optical, scintillation, and light yield properties. In NAPGCe glasses, intense emission peaks were observed at 312 nm (6P7/2 → 8S7/2) for Gd3+ and 336 nm (5d → 4f) for Ce3+ ions in both photoluminescence (275 and 294 nm) and radioluminescence (X‐ray) spectra. Upon excitation with 275 nm ultraviolet radiation, a decrease in Gd3+ emission and an increase in Ce3+ emission intensity lead to efficient energy transfer (ET) from Gd3+ to Ce3+ ion in NAPGCe glasses. The bi‐exponential function was applied to fit the non‐exponential decay curves of NAPGCe glasses and then calculated their lifetimes in the order of fast (18.25–16.94 ns) and slow (72.99–67.74 ns) decay times. An overall integrated scintillation efficiency of about 67% was estimated for NAPGCe0.10 glass compared to bismuth germanate oxide (BGO:Bi4Ge3O12) crystal. Under 241Am α‐ray (5.5 MeV) source, the light yield of the NAPGCe1.00 glass was obtained by comparing it with a commercial Li‐glass scintillator (GS20), and it was found to be 26 photons MeV−1. [ABSTRACT FROM AUTHOR]