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• CaNb 2 O 6 , as a new intrinsic scintillator was firstly reported. • The influences of the growth atmosphere on the optical and scintillation properties were investigated. • Crystals grown in an O 2 atmosphere displayed higher quantum efficiency, X-ray luminescence intensity, light yield, and lower afterglow. Single crystal CaNb 2 O 6 was grown by the optical floating-zone method and characterized for a new intrinsic scintillator. Under Ar and O 2 growth atmospheres, the as-grown crystal rods (Ф 4–5 mm) exhibit a greyish and a colorless appearance, respectively, which are related with the oxygen vacancy. They both show a broad emission band with the maximum at 480 nm under UV excitation, while the one grown in O 2 is brighter with a photoluminescence quantum efficiency of 44%. Consequently, a 25% higher scintillation light yield was obtained in the crystals grown in O 2 compared to those in Ar. The other scintillation properties including radioluminescence spectrum, pulsed X-ray decay and afterglow were also characterized and compared. [ABSTRACT FROM AUTHOR]

• Eu concentration dependences of SrI 2 :Eu properties are analyzed. • Energy resolution better 4% sustains even at Eu concentration as low as 0.3 at%. • Scintillation properties of SrI2:Eu do not depend on growth method (Czochralski or Bridgman). SrI 2 :Eu crystals with the activator content of 0.1–5.5% were grown by the Bridgman-Stockbarger technique. The dependences of light yield, energy resolution, optical and luminescent properties on the Eu concentration have been studied. It has been shown that with a decrease in the amount of activator to 0.3% Eu, the energy resolution at 662 keV remains below 4%. The light yield gradually diminishes with decreasing Eu concentration. This makes it possible to revise the required amount of the expensive activator for growing high performance SrI 2 :Eu crystals. Scintillation parameters of crystals grown by the Czochralski and Bridgman-Stockbarger technique have been compared. [ABSTRACT FROM AUTHOR]

• W co-doped Ce:Gd 3 Ga 3 Al 2 O 12 with 30–60 mm length grown by micro-pulling down method. • Light yield value was increased by small amount (200–1000 ppm) of W co-doping. • When the co-doping concentration of W was higher than 1000 ppm, the light yield decreased. Single crystal scintillators are extensively used in various radiation detection applications and their scintillation performances can be improved via co-doping. Therefore, in this study, tungsten-ion co-doped Ce:Gd 3 (Ga,Al) 5 O 12 (Ce:GGAG) crystals were grown using the micro-pulling-down (μ-PD) method to investigate the effects of co-doping on their scintillation properties. The relationships between the W concentration, optical and luminescence properties, and radiation response of the W-co-doped Ce:GGAG crystals were evaluated. The W-co-doped Ce 0.5%:Gd 3 Ga 3 Al 2 O 12 single crystals of diameter 3 mm and length 30–60 mm were grown by the μ-PD method. The light yield increased at W concentrations of 200 and 500 ppm and decreased at W concentrations above 1000 ppm. There was no significant change in the fast decay component of scintillation. [ABSTRACT FROM AUTHOR]

• Cs 2 HfCl 6 single crystal preparation by miniaturized and standard Bridgman methods. • Cs 2 HfCl 6 single-phase proved by XRD measurements. • Room temperature optical, luminescence, and scintillation properties of Cs 2 HfCl 6. • Room temperature photoluminescence and scintillation decay kinetics of Cs 2 HfCl 6. Time and cost effective methods are highly desirable in research and development of new scintillators. Modern techniques like micro-pulling down (μ-PD) are suitable for material screening but are unfit for the growth of some crystals. These crystals must be grown by different methods that are usually very time demanding. Modification of halide μ-PD apparatus by custom made elements allowed us to grow cesium hafnium chloride (Cs 2 HfCl 6) by vertical Bridgman method (VB) with significantly reduced growth time. Structural and optical properties of samples prepared from as-grown crystals were studied and compared to crystals grown by standard VB method. The X-ray diffraction confirmed the formation of cesium hafnium chloride single-phase and natural cleavage of the crystals along the (1 1 1) crystallographic plane. Photoluminescence emission, excitation, absorption, and radioluminescence spectroscopy revealed that the optical quality of the crystals grown by modified VB method was comparable to the quality of the crystals grown by standard VB method. Therefore we can use samples prepared by modified VB to estimate and optimize the performance of Cs 2 HfCl 6 based crystals in scintillation detectors. This setup allows the time and cost-effective material screening and it is a powerful tool for the development of new halide based single crystal scintillators. [ABSTRACT FROM AUTHOR]