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New single crystals of Ce-doped (1% and 10%) \ Tl_2\ LiYCl_6 (TLYC) were investigated under X-ray and $\gamma $-ray excitation. This material belongs to Chloro-elpasolite crystal family and was grown by the two-zone vertical Bridgman technique. X-ray-induced luminescence shows typical \ Ce^3 + - \ ion emission between 350 and 530 nm peaking at 430 nm. Under 662 keV \gamma $-rays excitation, best energy resolution of 4.8% (FWHM) was found for 1% Ce-concentration. For the same Ce-concentration, a maximum light yield of \sim $30 500 \pm $ 3500 ph/MeV was observed at room temperature. Under \gamma , respectively. Due to highly hygroscopic nature of this compound, extra attention was devoted during handling and data taking processes. Overall, the scintillation properties confirm that this material is a promising candidate for medical imaging and radiation detection. [ABSTRACT FROM AUTHOR]

The simultaneous measurement of heat and light signals from a ^40Ca ^100 MoO_4 scintillating crystal was performed at temperatures of tens of milli-kelvin using a scintillating bolometric detector. The crystal was instrumented with a pair of low-temperature detectors, consisting of a metallic magnetic calorimeter for reading the phonon signals and a light detector based on a Ge light absorber, to simultaneously measure the scintillation light and phonon signals. This article presents the principle and performance, such as the event separation capability, of this simultaneous heat/light measurement system. [ABSTRACT FROM AUTHOR]

Ce^3+ doped single crystals of Li6Lu0.5Gd0.5{(BO3)_3} (LLGBO) are grown by Czochralski method. We present the first report on this new mixed crystal of LLBO and LGBO (LLGBO). Powder X-ray diffraction (XRD) analysis confirmed single phase of the grown crystal. Under X-ray and laser excitation, similar emission between 350 nm and 550 nm is observed. Scintillation properties are measured which include: energy resolution, \alpha /\beta ratio and decay time. Energy resolution of 19% and 11% (FWHM) are observed under \gamma -ray (662 keV, ^137Cs) and \alpha -particles (5.5 MeV, ^241Am), respectively. Three decay time components are observed under \gamma -ray excitation at room temperature. [ABSTRACT FROM PUBLISHER]

New single crystals of Ce-doped Cs2NaGdCl6 are investigated under x-ray and \gamma-ray excitation. These scintillation crystals are grown by two zone vertical Bridgman technique and belong to elpasolite crystal family. Energy resolution, scintillation light yield, non-proportionality, energy resolution as a function of \gamma-rays energies and scintillation decay time measurements are presented. Ce^3+-related x-ray excited emission is observed between 360 and 450 nm wavelength region at room temperature. At higher Ce-concentration both self-trapped exciton (STE) and Gd^3+ emissions are disappeared and enhance Ce^3+ emission. Under 662 keV \gamma-rays excitation, Cs2NaGdCl6 shows an energy resolution of 5.2%, (FWHM) at 1% Ce-concentration. Best energy resolution of 4.8% (FWHM) is obtained for 10% Ce-concentration. No significant improvement is observed in the energy resolution of Cs2NaGdCl6 with the increase of Ce-concentration. The highest light yield of about 21,000 ph/MeV is obtained for 10% Ce-doped crystal. At room temperature three decay time components are found under \gamma-ray excitation for all Ce-doped samples. This material is highly hygroscopic. [ABSTRACT FROM PUBLISHER]

Li6Lu({BO_3)_3}{:}Eu^{3+} and Li6Lu({BO_3)_3}{:}Sm^{3+} are produced by solid state reaction. We have synthesized and characterized the luminescence of their properties for the first time. Firstly, we confirmed the structure and shape of Li6Lu({BO_3)_3}{:}Eu^{3+}, Sm^3+ phosphor using X-ray diffraction. Secondly, we optimized doping concentrations of activators. The lithium lutetium borate has a high effective atomic number (Zeff=52) and the molecular weight is 393 g/mol. Hence, it is considered that the efficiency of absorption is high in comparison to that of commonly used phosphor in X-ray imaging. [ABSTRACT FROM PUBLISHER]

The scintillation properties of Rb2LiCeCl6, a new scintillation material of the elpasolite family, are presented. Under X-ray excitation, broad emission band between 350 to 401 nm wavelengths is obtained. Such emission is attributed to cerium ion. The energy resolution of 662-keV photopeak measured with Rb2LiCeCl6 crystal is found to be 7.9% (FWHM). A maximum light yield of \sim 23\ 100 ph/MeV is measured. Under \gamma-ray excitation, Rb2LiCeCl6 single crystal showed two exponential decay time components. Comparison of X-ray excited emission and pulse height spectra of Rb2LiCeCl6 and Rb2LICeBr6 are also presented. Non-proportionality and energy resolution as a function of \gamma-rays energies are presented. This material is highly hygroscopic. [ABSTRACT FROM PUBLISHER]

Scintillation properties and radioactive contamination of calcium molybdate scintillating crystals depleted in ^48Ca and enriched in ^100Mo (^40Ca^100MoO4) have been studied to prepare a ^100Mo-based neutrinoless double beta decay experiment. The prospects of a neutrinoless double beta decay experiment using ^40Ca^100 MoO4 crystals are discussed. [ABSTRACT FROM PUBLISHER]

Search for neutrino-less double beta decay of 100Mo is proposed using active method with Ca 100MoO4 scintillation crystals which show the brightest scintillation light among variety of inorganic scintillation materials containing Mo. Study of X-ray luminescence and scintillation properties such as energy response, number of photoelectrons/keV, absolute light yield, decay time, pulse shape discrimination and radioactive contamination of CaMoO4 crystals grown by the Czochralski method with different conditions are presented. Further R&D of resolution optimization, crystal quality improvement and background reduction are underway. Significant improvement of sensitivity to neutrino-less double beta decay can be achieved by using 100Mo enriched Ca 100MoO4 crystals with good energy resolution and low background. Further reduction of background induced by 48Ca two neutrino double beta decay can be achieved by using 48Ca depletion. We are planning to install several kilograms of Ca100MoO4 crystals depleted in 48Ca at underground laboratory for the neutrino-less double beta decay experiment in the near future. [ABSTRACT FROM AUTHOR]

In this work, we present the crystal growth and scintillation properties of our newly developed scintillation crystal, Cs2 LiCeCl6, for a γ-ray spectroscopy. This scintillation crystal is grown by using the vertical Bridgman method. The crystal of this material belongs to the elpasolite family characterized by a cubic structure and potentially can be easily grown in large volumes. Under the X-ray excitation, cerium emission band is observed to peak at 385 nm and 405 nm. An energy resolution (full width at half maximum over the peak position) of 5.5 % was observed for the 662 keV full absorption peak. We measured an absolute light yield of 22 000 photons/MeV of absorbed γ-ray energy. The crystal shows three main scintillation decay time components of 101 ns (42%), 557 ns (35%) and 2.9 µs (23%). This material is highly hygroscopic and special attention was paid during data taking and handling processes. We believe that the Cs2 LiCeCl6 crystal can be a promising material for medical imaging and radiation detection. Moreover due to the presence of Li ions, this scintillation crystal can also be a possible candidate for thermal neutron detection. [ABSTRACT FROM AUTHOR]

In this work, we present the crystal growth and scintillation properties of our newly developed scintillation crystal, Cs2 LiCeCl6, for a γ-ray spectroscopy. This scintillation crystal is grown by using the vertical Bridgman method. The crystal of this material belongs to the elpasolite family characterized by a cubic structure and potentially can be easily grown in large volumes. Under the X-ray excitation, cerium emission band is observed to peak at 385 nm and 405 nm. An energy resolution (full width at half maximum over the peak position) of 5.5 % was observed for the 662 keV full absorption peak. We measured an absolute light yield of 22 000 photons/MeV of absorbed γ-ray energy. The crystal shows three main scintillation decay time components of 101 ns (42%), 557 ns (35%) and 2.9 µs (23%). This material is highly hygroscopic and special attention was paid during data taking and handling processes. We believe that the Cs2 LiCeCl6 crystal can be a promising material for medical imaging and radiation detection. Moreover due to the presence of Li ions, this scintillation crystal can also be a possible candidate for thermal neutron detection. [ABSTRACT FROM AUTHOR]

In this paper crystal growth, luminescence and scintillation properties of Cs2NaCeBr6 crystal are presented. The studied Cs2NaCeBr6 crystal was grown by the Bridgman method using a two-zone vertical transparent furnace. The material was synthesized using the reaction 2CsBr + NaBr + CeBr3 → Cs2NaCeBr6. Under UV excitation the emission of crystal was observed in the range of 300 to 450 nm with two peaks at 377 and 400 nm. The emission is due to the 5d → 4f transitions on Ce3+. The energy resolution of the crystal measured under 662 keV was 6.7%. The scintillation decay time showed two components characterized by 140 ns and 880 ns time constants. The light yield of the crystal was estimated to be 25,000 photons/MeV. [ABSTRACT FROM AUTHOR]

We present the luminescent and scintillation characteristics of CsI:CO3 single crystals. The CsI:CO3 single crystals were grown by using Czochralski method for different concentrations of CO3 from 0.007 to 0.1 mole%. The crystals were cut into a size of 10 mm x 10 mm x 5 mm. The luminescent characteristics were measured with X-rays to study the emission spectra of the CsI:CO3 crystals. The scintillation properties of the CsI:CO3 crystals such as fluorescence decay time, energy resolution, pulse height spectra, proportionality, and relative light output were studied by using various y-ray sources with a photomultiplier tube (PMT) at room temperature. The absolute light outputs of the crystals were also measured with an avalanche photo-diode (APD). [ABSTRACT FROM AUTHOR]

We grew a Gd-doped lead chloride single crystal by the Bridgman method and investigated scintillation properties of the crystals at low temperature. We measured the relative light yield, energy resolution, fluorescence decay time, and proportionality of the crystals for the γ-ray at low temperature. The energy resolution is measured to be 25.6% for the 137Cs 662 keV γ-ray, and the fluorescence decay time of the crystal is composed of two components with decay times of 1.35 and 6.20 µs at 173 K. [ABSTRACT FROM AUTHOR]

In this paper, we present scintillation properties of the new developed single crystals of BaxSr1-xCl2for different concentration of x. We manufactured Ba0.12Sr0.88 Cl2, Ba0.20Sr0.88Cl2, Ba0.20Sr0.80Cl2 crystals, and CsI(Tl) crystal as reference by using the Czochralski method. The crystals were cut into a size of 5 × 10 × 10 mm³. The X-ray diffraction technique was used to verify the structure of crystals. The emission spectra were measured with X-ray excitation at room temperature. Scintillation properties of the crystals such as pulse height spectra, energy resolution, α/β ratio, relative light output, proportionality, and fluorescence decay time were measured with the various radioactive γ sources at room temperature. The light output of these crystals were compared with that of the CsI(Tl) crystal. The differences in relative light outputs, energy resolutions, and decay times among these crystals were studied in detail. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop scintillation crystals for the study of neutrinoless β+/EC decay process. The 84Sr isotope is one of the potential candidates for the neutrinoless β+/EC decay process. None of the scintillation crystals containing a strontium element up till now were used for the study of neutrinoless β+/EC decay process. In general our crystal growth program include studies of starting material preparation, growth procedures and characterization of grown crystals. We grew a SrCl2 single crystal by using Czochralski method. The cylindrical shape of the SrCl2 crystal was cut into the dimensions of Φ 2 × 1.5 cm³. The scintillation properties were studied by using various gamma ray sources and an alpha source. The scintillation properties such as energy resolution, light output, linearity and decay time were presented. In particular, the α/β light ratio and possibility of a pulse shape discrimination between α and γ quanta using 210 Po alpha source were studied. [ABSTRACT FROM AUTHOR]

Scintillation properties of calcium molybdate are investigated. The emission spectrum is broad with a maximum at 520 nm. At room temperature the light yield is 4% of CsI(TI) (400 photoelectrons/MeV) and the decay lime is 17 μs. During cooling the light yield and decay lime increase. Prospects of optimization of this scintillator are also discussed. The feasibility of the material for the search of neutrinoless double beta decay of 100Mo is analyzed. A half life limit of T½ = 1.1025 years (68% CL) seems feasible with CaMoO4 scintillator, running with 10 kg of 100Mo for 5 years. The background due to two neutrino double beta decay of 48Ca is also considered. Requirements for new scintillators for double beta decay search are formulated. [ABSTRACT FROM AUTHOR]