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LaMgAl 11 O 19 :Er single crystals were examined as candidates for scintillators emitting near-infrared luminescence, and their radioluminescence and scintillation detector characteristics were assessed. Upon exposure to X-ray, distinct emission peaks appear at ∼550 and ∼1540 nm and are attributable to Er3+ ions. The decay curves also exhibited characteristic decay times associated with Er3+ ions. Particularly, the 3% Er-doped sample showed a discernible linearity in the dynamic range of dose rate from 1 to 50,000 mGy/h, indicating the potential utility in applications requiring precise and reliable radiation measurements. • Er-doped LaMgAl 11 O 19 crystals were synthesized by the floating zone method. • The samples show a broad emission band at 380 nm due to host and sharp peaks at 550 and 1540 nm due to Er3+. • The 3% Er-doped sample showed a good linearity in the dynamic range of dose rate from 1 to 50,000 mGy/h. [ABSTRACT FROM AUTHOR]

Ce differently (0, 0.01, 0.1, 1, 2 and 5% with respect to Mg) doped LiMgAlF 6 ceramics were synthesized by the spark plasma sintering (SPS) method. In photoluminescence (PL), emission bands appeared at 300 nm with 30 ns day time, and these emission properties were almost the same in scintillation under X-ray irradiation. Further, thermally stimulated luminescence (TSL) was observed after X-ray irradiation, and the primary glow peak temperature was 160 °C with a lower detection limit of ∼10 mGy. • Ce-doped LiMgAlF 6 ceramics were prepared by the spark plasma sintering method. • Photoluminesence and scintillation properties were investigated. • Thermally stimulated luminescence properties were evaluated. [ABSTRACT FROM AUTHOR]

BaCl 2 :Eu transparent ceramics were synthesized by the spark plasma sintering method, and concentration dependence of Eu on optical and scintillation properties was investigated. BaCl 2 :Eu transparent ceramics showed photoluminescence (PL) and scintillation peaks at 400 nm due to 5d–4f transition of Eu2+. The PL and scintillation decay time constants of BaCl 2 :Eu transparent ceramics were ∼400 ns. The PL quantum yields (QY s) of 0.05, 0.1, 0.5, and 1% BaCl 2 :Eu transparent ceramics were 28.5, 25.6, 16.2, and 13.9%, respectively. The afterglow levels of BaCl 2 :Eu transparent ceramics were lower than CsI:Tl single crystal in practical use. The scintillation light yield of the 0.5% doped BaCl 2 :Eu transparent ceramic was 9800 photons/MeV when γ-rays by 137Cs were irradiated. • BaCl 2 :Eu transparent ceramics were synthesized using the SPS method. • We investigated the optical and scintillation properties. • The scintillation peak due to 5d–4f transition of Eu2+ was observed at 400 nm. • The 0.5% Eu-doped sample showed the highest LY (9800 ph/MeV) under 137Cs γ-ray irradiation. [ABSTRACT FROM AUTHOR]

Pr:Li 6 Y(BO 3) 3 and Pr,Ce:Li 6 Y(BO 3) 3 crystals were grown by the Czochralski method. The luminescence properties of the Pr:Li 6 Y(BO 3) 3 and Pr,Ce:Li 6 Y(BO 3) 3 crystals, such as their optical transmission, photoluminescence and X-ray induced luminescence spectra were investigated. The scintillation properties of the multi-channel energy spectrum of the Pr,Ce:Li 6 Y(BO 3) 3 crystal under thermal neutrons and gamma-ray excitation were also studied. The energy resolutions of the Pr,Ce:Li 6 Y(BO 3) 3 crystal, which had a size of 8 × 7 × 2 mm3 , excited by moderated 252Cf for the 10B (n,α)7Li and 6Li (n,α)3H reactions were determined to be 42% and 16%, respectively. The decay time under 320 nm UV light excitation was fitted to be 27 ns. Therefore the Pr,Ce:Li 6 Y(BO 3) 3 crystal is a promising fast scintillator for thermal neutron detection with good energy resolution, fast decay time and possible pulse-height discrimination ability. • Pr3+, Ce3+ co-doped Li 6 Y(BO 3) 3 crystals were grown using Czochralski method. • The energy resolution of Pr,Ce:LYBO crystal for 10B (n,α)7Li reaction is 42%. • The energy resolution of Pr,Ce:LYBO crystal for 6Li (n,α)3H reaction is 16%. • The photoluminescence decay time of Pr,Ce:Li 6 Y(BO 3) 3 crystal is 27 ns. [ABSTRACT FROM AUTHOR]

Abstract In this study, the Gd3+-substituted yttrium aluminum perovskite epitaxial films activated by Ce3+ ions, (YGd)AlO 3 :Ce3+ with Gd content 0–44%, were prepared by liquid phase epitaxy technique and their optical, luminescence, and scintillation properties were studied. The results showed that films with Gd content below 20% had greater photoluminescence and radioluminescence intensities. For higher Gd concentrations, the Ce3+ emission gradually decreased and the Ce3+ decays were accelerated. The model of bidirectional non-radiative energy transfer between Gd3+ and Ce3+ ions and energy migration over the Gd3+ sublattice is suggested and the processes responsible for the observed effects are discussed. Highlights • (GdY)AlO 3 :Ce3+ perovskite scintillators were characterized. • Bidirectional Gd3+-Ce3+ energy transfer in GdYAP:Ce perovskite was proposed. • Gd co-doped YAlO 3 :Ce3+,Gd3+ perovskite films were prepared by liquid phase epitaxy. [ABSTRACT FROM AUTHOR]

Abstract LaAlO 3 perovskite single crystals doped with Ce, Eu or Tb have been grown by micro-pulling-down method. X-ray diffraction analysis confirmed low-temperature rhombohedric phase. Energy-dispersive Laue mapping revealed sub-grains in the grown crystals. For the Ce-doped crystals, very low radioluminescence efficiency was found and the observed emission was ascribed to defects. Photoluminescence spectra were significantly different from the radioluminescence ones. They were significantly quenched at room temperature and the related luminescence showed also unusually high Stokes shift. High radioluminescence efficiency was found for the Tb-doped samples and especially for the Eu-doped ones, which would point to the fact that in LaAlO 3 the scintillation process is more favorable for the luminescence ions which tend to capture an electron first. Highlights • Morphology of the grown rare-earth-doped LaAlO3 crystals was studied. • Role of the growth atmosphere explained by its influence on Ce valence state. • Origin of radioluminescence explained by defect emission in Ce-doped crystals. • High radioluminescence efficiency found for Eu-doped crystals. [ABSTRACT FROM AUTHOR]

The linear response is the key property employed by a radiation detector to determine the accurate intensity of a pulse radiation field. In this study, we investigated the high fluence rate response behavior of a LaBr 3 scintillator. We used a high-intensity pulsed X-ray source called “QiangGuang-I” which could produce an X-ray pulse with a total dose of 100 Gy, full width at half maximum of 20 ± 5 ns, and an average energy of 1 MeV, to test the linear response of the LaBr 3 scintillator. The Lissajous figure method was used in this experiment. The results showed that the fluence rate linear response limit was more than 1.8 × 10 20 MeV/(cm 2 ·s). [ABSTRACT FROM AUTHOR]

We have synthesized the Al 2 O 3 transparent ceramic by using spark plasma sintering (SPS) and investigated the dosimeter and scintillation properties for X-ray detections, in comparison with the single crystal. Under X-ray irradiation, emissions at 300, 400 and 693 nm were observed in both the samples. To identify the origins of these emissions, scintillation decay times were investigated. Based on the results, emissions at 300, 400 and 693 nm are attributed to F + centers, F centers and Cr 3+ impurity ions, respectively. The thermally-stimulated luminescence (TSL) glow curves of both the samples showed a main peak around 50 °C. In addition, glow peaks were observed at 190, 290 and 360 °C. The TSL spectra had broad emission bands in the 300, 400 and 693 nm, which approximately agreed with the scintillation spectra. The TSL response was confirmed to be linear to the irradiation dose for transparent ceramic over the dose range from 0.3 to 1000 mGy while the sensitivity of the single crystal was lower and the response range confirmed was from 30 to 1000 mGy. [ABSTRACT FROM AUTHOR]

Over the past two decades, substantial research has been done on the typical elpasolite scintillators Ce:Cs 2 LiYCl 6 (CLYC) and Ce:Cs 2 LiLaBr 6 (CLLB) for their potential use as neutron/gamma dual-mode detectors. Commonly, the cation or anion alloying will change the luminescence and scintillation properties of the scintillators, such as the good energy resolution of the Ce:Cs 2 LiLa(Br–Cl) 6 (CLLBC) crystal. In this work, ⌀8 mm Ce:Cs 2 Li(LaBr 6) x (YCl 6) 1-x crystals with x = 0.1, 0.2, 0.3 and 0.4 were grown by the vertical Bridgman technique. Then, ⌀25 mm Ce:Cs 2 LiLa 0.1 Y 0.9 Br 0.6 Cl 5.4 crystal was grown for its relatively high optical quality and phase purity. The luminescence and scintillation properties were also investigated. The energy resolution of Ce:Cs 2 LiLa 0.1 Y 0.9 Br 0.6 Cl 5.4 crystal was calculated to be 9.3%. The scintillation decay time were 38 ns and 623 ns under 137Cs irradiation. • Ce: Ce:Cs 2 Li(LaBr 6) x (YCl 6) 1-x crystals were grown using vertical Bridgman method. •⌀25 mm Ce:Cs 2 LiLa 0.1 Y 0.9 Br 0.6 Cl 5.4 crystal with good optical quality was obtained. • Energy levels were calculated and CVL mechanism was displayed. •The photoluminescence decay time of Ce:Cs 2 LiLa 0.1 Y 0.9 Br 0.6 Cl 5.4 crystal was 36.9 ns. •Energy resolution of 9.3% under 137Cs irradiation was obtained. [ABSTRACT FROM AUTHOR]

The emissions of Ce3+ in Ce:YAG are at approximately 550 nm and are generated by the overlapping emission of two transitions 5d → 2F 5/2 (2F 7/2), and their luminescence characteristics are markedly influenced by temperature and ion fluence. In this study, the temperature and ion fluence dependence of Ce3+ emission was investigated using ion beam-induced luminescence (IBIL) at four different temperatures (25, 150, 300, and 450 °C), and potential theoretical explanations for the variation were discussed. Experimental results show that (1) as the temperature increases, the intensity of Ce3+ decreases, and the central peak position continues to redshift; (2) as the temperature rises, the proportion of the high-energy peak at approximately 2.3 eV continuously increases; (3) a double exponential model can describe the evolution of the Ce3+ luminescence intensity with fluence; and (4) the influence of 2 MeV H+ on the luminescence characteristics of Ce:YAG is limited. The luminescence characteristics of the Ce:YAG single crystal deteriorate when exposed to high temperatures. Combined with the observed experimental phenomena, we recommend that the practical operating temperature of the Ce:YAG single crystal in a high ion fluence environment should be as low as 150 °C when possible to ensure a high scintillation yield and good luminescence performance. • Acquiring real-time and in-situ luminescent data on Ce:YAG single crystal with IBIL. • Temperature has a significant influence on Ce:YAG performance than fluence. • Ionic excitation allows thermal quenching of Ce3+ at lower temperatures. • Evaluating the radiation resistance of samples with double exponential model. • The working temperature of Ce:YAG should not exceed 150 °C in high ion fluence. [ABSTRACT FROM AUTHOR]

The luminescence and scintillation properties of Lu 0.8 Gd 1.2 SiO 5 :Ce and Lu 1.8 Gd 0.2 SiO 5 :Ce single crystals are compared. At 662 keV γ-rays, light yield (LY) value of 29,800 ph/MeV obtained for Lu 1.8 Gd 0.2 SiO 5 :Ce is much higher than that of 20,200 ph/MeV obtained for Lu 0.8 Gd 1.2 SiO 5 :Ce. The energy resolution of 6.0% obtained for Lu 0.8 Gd 1.2 SiO 5 :Ce is better than that of 7.7% for Lu 1.8 Gd 0.2 SiO 5 :Ce due to its better intrinsic resolution and proportionality of LY. The LY and energy resolution for α-rays, as well as a LY ratio under excitation with α- and γ-rays (α/γ ratio) are also determined. The intrinsic LY and light loss coefficient under excitation with α- and γ-rays are evaluated. The photofraction at 662 keV γ-rays is also determined and discussed. [ABSTRACT FROM AUTHOR]

Fluoroborosilicate (SBF anc :SiO 2 + B 2 O 3 +AlF 3 + NaF + CaF 2) glasses with different CeF 3 concentrations were fabricated by melt quenching technique to examine the scintillation properties of these glasses. The density and refractive index increase with an increase in CeF 3 concentration. The structural properties of glasses were studied in the range of 800–4000 cm−1 using FT-IR transmittance spectroscopy. Luminescence characteristics of Ce3+:SBF anc glasses with an intensity peak around ∼345 nm (5d→4f) were studied using photo (λ exc = 303 nm) and X-ray excited luminescence techniques. The energy transfer (ET) between Ce3+ -Ce3+ ion pairs taking place via dipole-dipole type interaction for the concentration quenching of Ce3+ emission on the basis of Dexter and Schulman theory. The PL decay curves can be fitted by a double exponential function with the decay times 64.28–99.87 ns and 15.78–21.29 ns for slow and fast decay components, respectively. The highest integrated light emission intensity of Ce3+:SBF anc glasses stimulated by X-ray is 35% of commercial Bi 4 Ge 3 O 12 crystal and can be used for the scintillator materials. • The transmittance spectra of glasses were measured in UV, Visible and mid-IR region. • Concentration quenching of Ce3+ emission is analyzed by the Dexter-Schulman theory. • PL, X-ray excited luminescence and decay curves of glasses were investigated. • The X-ray intensity of SBF anc Ce 0.30 glass is about 35% of that of a commercial BGO. [ABSTRACT FROM AUTHOR]

In this work, the Ce 3+ doped gadolinium-calcium-silicaborate glass scintillators of the composition ratio 25Gd 2 O 3 :10CaO:10SiO 2 :(55−x)B 2 O 3 :xCeF 3 , have been fabricated by using the melt-quenching technique. The doping concentration of the Ce 3+ was varied from 0.05 mol% to 2.5 mol%. The 4f-5d transition of the Ce 3+ allowed scintillation with a fast decay time. The absorption spectrum, X-ray induced emission spectrum, photo luminescence spectrum, laser luminescence spectrum and decay time of the scintillators were measured for studying the luminescence properties. From the X-ray induced emission spectrum result, we checked the trend between doping concentration and light yield. The laser induced luminescence spectrum was measured while changing the temperature from 300 K to 10 K. We also measured the decay time by using the laser excitation of the 0.15 mol% Ce 3+ doped glass scintillator. [ABSTRACT FROM AUTHOR]

1300 or 1400 °C pre–sintered Al/Ce/Mg:SrHfO 3 and Al/Ce:SrHfO 3 ceramics were prepared by the Spark Plasma Sintering (SPS) in order to search for a new scintillation material with a high–effective atomic number(Z eff ) and good light output. The SrHfO 3 has a high Z eff of 60, and high gamma–ray detection efficiency is expected. Meanwhile it has a high melting point of over 2500 °C, and single crystal is hard to be grown. On the other hand, high melting materials can be prepared as ceramics, and the SPS method is a simple process to fabricate the ceramics within a few hours. Thus, we prepared the samples using the SPS method, and their optical and scintillation properties were investigated. We found that Al/Ce/Mg:SrHfO 3 and Al/Ce:SrHfO 3 ceramics had an emission wavelength at around 400 nm originating from 5d–4f transition of Ce 3+ . Moreover, Al/Ce/Mg:SrHfO 3 pre-sintered at a temperature of 1400 °C had a light output of approximately 5,000 ph/MeV. In this paper, the light output of Mg-co-doped samples was improved compared with the Mg-free ones. The light output also depends on the pre-sintering temperature. [ABSTRACT FROM AUTHOR]

It was shown that annealing ZnO and ZnO:Ga initial powders and ceramics in different atmospheres significantly changes the characteristics of the studied samples. Two main luminescence bands of different origins were observed in powders at 540 nm and 580 nm. Annealing either in vacuum or in Ar:H 2 atmosphere increased intensity of green luminescence with peak at 540 nm whereas annealing in air enhanced a luminescence band with peak at 580 nm in the powders. Corresponding changes in luminescence kinetic properties were observed. Annealing of the ceramics in vacuum and air did not affect the luminescence properties, while annealing them in Ar:H 2 atmosphere increased green luminescence intensity of undoped ceramics and excitonic luminescence intensity of doped ones. Comparison of the X-ray, gamma-ray and cathode-ray excited luminescence lead to conclusion that the enhancement of luminescence intensity took place in surface layer of about 100 μm thickness. [ABSTRACT FROM AUTHOR]

The luminescence and scintillation properties of YGd 2 Al 2 Ga 3 O 12 :Ce and LuGd 2 Al 2 Ga 3 O 12 :Ce single crystal scintillators were compared. The light yield (LY) and energy resolution were measured using R6231 photomultiplier. At 662 keV γ-rays, high LY value of 37,900 ph/MeV and energy resolution of 7.0% obtained for YGd 2 Al 2 Ga 3 O 12 :Ce are slightly better than the values of 35,400 ph/MeV and 7.6% obtained for LuGd 2 Al 2 Ga 3 O 12 :Ce. The ratio of LY values under excitation with α- and γ-rays (α/γ ratio) was also determined. The LY dependence on amplifier shaping time was measured in order to investigate the timing characteristics in the scintillation response. The estimated photofraction in pulse height spectrum of 662 keV γ-rays and the total mass attenuation coefficient at 662 keV γ-rays were also determined and compared with the theoretical ones calculated using the WinXCom program. [ABSTRACT FROM AUTHOR]

The paper is devoted to investigation of the luminescent properties of Dy 3+ and Dy 3+ -Ce 3+ doped single crystalline films (SCF) grown by LPE method from PbO–B 2 O 3 flux. We have found that the YAG:Dy and YAG:Dy,Ce SCFs possess bright cathodoluminescence in the visible range and good scintillation figure of merit. For this reason LPE grown YAG:Dy and YAG:Dy,Ce SCF are proposed for different applications, namely, as cathodoluminescence screens or screens for microimaging. The Dy 3+ co-doping can be also proposed for improvement of the scintillation efficiency of the Ce 3+ doped garnet compounds in the SCF form due to Dy 3+ → Ce 3+ energy transfer and removing the trap related centers in the above RT range. [ABSTRACT FROM AUTHOR]

In recent years, there has been increasing demand for a scintillator showing near-infrared (NIR) luminescence owing to the potential for radiation monitoring applications. In this study, Pr-doped Bi 4 Ge 3 O 12 (BGO) single crystals were prepared by the floating zone method to explore candidates as a NIR scintillator, and the luminescence and dose-rate response properties of Pr-doped BGO were studied. Both photoluminescence and scintillation peaks appeared at 400–600 nm due to Bi3+, and sharp emission peaks by Pr3+ were also confirmed at 480–1100 nm, with consistent decay times. Further, to investigate performance as a scintillation detector, a linearity of the response to X-ray exposure dose rate was evaluated. Among the samples, the 0.5% Pr-doped BGO showed the highest sensitivity with the lowest detection limit of 0.006 Gy/h. • ● Pr-doped Bi 4 Ge 3 O 12 single crystals were grown by the floating zone method. • The emission due to Pr3+ 4f–4f transitions was observed in the visible–NIR range. • The NIR scintillation intensity was proportional to the X-ray exposure dose rate. • The lowest detection limit was 0.006 Gy/h when the 0.5% Pr-doped sample was used. [ABSTRACT FROM AUTHOR]

The luminescence and scintillation properties of ZnMo 1-x W x O 4 (x = 0, 0.0022, 0.0088) crystals grown by low thermal gradient Czochralski technique were studied in a temperature range of 10–300 K. The good optical transparency above the fundamental absorption of crystals were obtained for all the samples. The luminescence light yield enhancement and slowing of the decay time were observed with lowering the temperature for W doped samples under 4.42 eV excitation. Improvement in scintillation light yield with W doping in ZnMoO 4 crystals was observed and found 76% that of ZnWO 4 crystal at 10 K for 0.88 mol% W doped ZnMoO 4 sample. An additional TSL band was observed for the W doped samples in the temperature range of 70–100 K. The enhancement in scintillation light yield at low temperature with W doping in ZnMoO 4 crystal are quite encouraging to use it as a cryogenic phonon scintillation detector for the neutrinoless double beta decay search of 100Mo. • Luminescence and scintillation of W doped ZnMoO 4 crystal are studied in 10–300 K. • The luminescence decay time becomes slow at low temperature with W doping. • The light yield improved significantly at 10 K with W doping in ZnMoO 4. • A TSL band was observed for W doped samples at low temperature. • The W doping in ZnMoO 4 improved optical quality and scintillation yield. [ABSTRACT FROM AUTHOR]

This study reports on the crystal growth, luminescence, and scintillation performance of a novel elpasolite K 2 LiCeCl 6 scintillator. The single crystal of this material was grown by the two-zone vertical Bridgman technique. The luminescence and scintillation performance were studied under X-, γ -rays, and α -particles excitation at room temperature. The fast scintillation response and α -particles and γ -ray separation capability reveal that this scintillator can be used as a dual-mode γ -rays and thermal neutron detector. • Novel elpasolite K 2 LiCeCl 6 crystal scintillator was developed. • The luminescence properties are studied by using various radiation sources. • Three decay time components were found. • Pulse shape discrimination with gamma-ray and alpha particle was measured. [ABSTRACT FROM AUTHOR]

We report the luminescence and scintillation properties of TlSr 2 Cl 5 crystals, which have a large effective atomic number (Z eff = 63.7), for application in X-ray and gamma ray detection. TlSr 2 Cl 5 crystals were prepared under vacuum using the self-seeding solidification method. The scintillation emission bands were observed at 430 and 490 nm, which are close to the emission wavelengths of TlMgCl 3 and TlCdCl 3. The peak wavelengths were characteristic of self-activated thallium-based chloride crystals. The scintillation decay time constants were estimated to be 7.5 ns (61%), 99 ns (7%), and 1375 ns (32%). These decay time constants are close to those of TlMgCl 3 and TlCdCl 3 and are also characteristic of self-activated thallium-based chloride crystals. The light yield of TlSr 2 Cl 5 was estimated to be approximately 19,000 photons/MeV, which is higher than that of Gd 2 SiO 5 (Ce) (GSO) (10,000 photons/MeV) and close to that of Lu 2 SiO 5 (Ce) (LSO) (27,000 photons/MeV). • TlSr2Cl5 scintillator having a large Zeff (= 63.7) was developed. • Scintillation spectra exhibited an intense emission band at 430 and 490 nm. • The light yield (19,000 photons/MeV) was higher than that of GSO (10,000 ph/MeV). [ABSTRACT FROM AUTHOR]

Tm-doped CaHfO 3 crystals were synthesized by the floating zone method equipped four xenon arc lamps, and the photoluminescence (PL), scintillation, and thermally-stimulated luminescence (TSL) properties were investigated. The Tm-doped samples exhibited intense sharp emission peaks at around 460 nm due to 4f–4f transitions of Tm3+. The PL and scintillation decay time profiles showed typical decay time constants of 4f–4f transitions of Tm3+. In TSL dose response, the minimum and maximum detection limit of the Tm-doped samples were 10 and 10000 mGy, respectively. • Undoped and Tm-doped CaHfO 3 crystals were synthesized by floating zone method. • Photoluminescence, scintillation, and TSL properties of CaHfO 3 crystals were investigated. • Tm-doped CaHfO 3 crystals exhibited sharp peaks at around 460 nm. • TSL glow peaks of Tm-doped CaHfO 3 crystals appeared at around 90, 140, and 240 °C. [ABSTRACT FROM AUTHOR]

Different concentrations of Eu doped LiMgAlF 6 samples were synthesized by the spark plasma sintering (SPS) method. In photoluminescence (PL) measurements, emission due to 5d-4f transition of Eu2+ was observed at 370 nm, and PL decay times resulted 1.1–2.8 μs. When we irradiated X-rays, scintillation emissions due to Eu2+ and Eu3+ were detected at 370 and 600 nm, respectively. Optically stimulated luminescence (OSL) and thermally stimulated luminescence (TSL) were also observed in Eu-doped LiMgAlF 6 , and especially, TSL intensity was very high. • We prepared Eu-doped LiMgAlF 6 ceramic by the spark plasma sintering method. • Photoluminescence and scintillation properties were investigated. • Optically and themelly stimulated luminescence properties were evaluated. [ABSTRACT FROM AUTHOR]