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A series of barium gadolinium borate glasses doped with Sm3+ ions in chemical composition of 20BaO:10Gd2O3:(70-x)B2O3: xSm2O3 were synthesized by melt quenching technique, at different Sm2O3 concentration varying from 0.0 to 1.5 mol%. The prepared glasses were systematically characterized their properties through density, molar volume, absorption, excitation and emission spectra. The density and molar volume of glasses increased with increasing of Sm2O3 in higher concentration. The absorption spectra show characteristic peaks of Sm3+ in visible and infrared regions. The emission spectra show the strongest reddish-orange emission at 598 nm under excitation at 403 nm. The CIE1931 chromaticity coordinate shows that all glasses emitted the orange color, which could be used as orange emitting material applications.

Dysprosium doped Li2O-SrO-GdF3-B2O3 (LSGB) glasses were prepared by the conventional melt quenching technique in order to study the luminescence properties and their utility for white light emitting diodes (LEDs). The glass structure was studied by X-ray diffraction (XRD) and Fourier transform infra-red (FT-IR) spectroscopy. XRD confirmed the amorphous structure of the glass samples. The FT-IR spectra revealed the presence of BO3, BO4 and non-bridging oxygen's. The optical absorption measurement were carried out in UV-VIS-NIR region. The PL emission and excitation spectra for the LSGB glasses were investigated. From the excitation and the emission spectra the highest Dy3+ excitation and emission intensities was observed for 0.5 mol% Dy3+-doped oxyfluoride glass. Strong blue (482 nm) and yellow (575 nm) emission bands were observed upon various excitations. These two emissions corresponds to the (4F9/2 → 6H15/2) and (4F9/2 → 6H13/2) transitions of Dy3+ ions, respectively. The blending of these blue and yellow bands gives white light. The CIE 1931 chromaticity coordinates for all the as made glass samples under various excitation wavelengths lies right in white region. The calculated correlated color temperature (CCT) values for the present oxyfluoride glasses were found in the range of 4336–4299 K. These were slightly more than warm CCT (i.e., CCT

Lutetium (Lu) is a high atomic number material and readily interacts with X-rays, which makes it a good scintillation material. In this work, Lu-glass scintillators from the series xSm2O3: 25Lu2 O3: 10SiO2: 10CaO: (55-x)B2O3 (LuCSB) were synthesized at 1500 ◦ C by using a simple melt quenching technique. The influence of the Sm3+ ion on their physical, optical, photo-, X-rayand proton-induced properties has been characterized. The amorphous nature of the samples was confirmed by using X-ray diffraction. The density and the molar volume were found to be increased at higher concentrations of Sm3+. The X-ray- and the proton-induced emission spectra of the Sm3+:LuCSB glasses showed an intense reddish-orange emission around 604 nm (4G5/2 → 6H7/2), which matched the photoluminescence (PL) emission spectrum well. Among the prepared glasses, the 1.0-mol% Sm3+ ion-activated LuCSB glass exhibited the highest value of the characteristic emission parameters. The X-ray-induced luminescence of the LuCSB glass was also compared with that of a commercial bismuth germinate Bi4Ge3O12 (BGO) crystal.

A calcium molybdate ( $\text{CaMoO}_{4}$ ) crystal scintillator, with molybdenum enriched in $^{100}\text{Mo}$ and calcium depleted in $^{48}\text{Ca}$ ( $^{40}\text{Ca}{}^{100}\text{MoO}_{4}$ ), was developed by the Advanced Molybdenum based Rare process Experiment (AMoRE) collaboration to search for a neutrinoless double beta ( $0\nu \beta \beta $ ) decay of $^{100}\text{Mo}$ . We are planning to use about 10 kg of $^{40}\text{Ca}{}^{100}\text{MoO}_{4}$ crystals as cryogenic bolometers for the first phase of the experiment (AMoRE-I) at the Yang Yang underground laboratory (Y2L) in Korea. This experiment calls for an extremely low level of radioactive contamination in detectors, particularly by thorium, uranium, and radium decay chains. We measured scintillation properties and radioactive contamination of $\text{CaMoO}_{4}$ and $^{40}\text{Ca}{}^{100}\text{MoO}_{4}$ crystals at the Y2L. We also estimated the acceptable level of internal radioactive background using Monte Carlo simulation for the AMoRE-I.

The advanced molybdenum-based rare process experiment (AMoRE) aims to search for neutrinoless double beta decay ($$0\nu \beta \beta $$0νββ) of $$^{100}$$100Mo with $$\sim 100\,\hbox {kg}$$∼100kg of $$^{100}$$100Mo-enriched molybdenum embedded in cryogenic detectors with a dual heat and light readout. At the current, pilot stage of the AMoRE project we employ six calcium molybdate crystals with a total mass of 1.9 kg, produced from $$^{48}$$48Ca-depleted calcium and $$^{100}$$100Mo-enriched molybdenum ($$^{48{{\text {depl}}}}\hbox {Ca}^{100}\hbox {MoO}_{4}$$48deplCa100MoO4). The simultaneous detection of heat (phonon) and scintillation (photon) signals is realized with high resolution metallic magnetic calorimeter sensors that operate at milli-Kelvin temperatures. This stage of the project is carried out in the Yangyang underground laboratory at a depth of 700 m. We report first results from the AMoRE-Pilot $$0\nu \beta \beta $$0νββ search with a 111 kg day live exposure of $$^{48{{\text {depl}}}}\hbox {Ca}^{100}\hbox {MoO}_{4}$$48deplCa100MoO4 crystals. No evidence for $$0\nu \beta \beta $$0νββ decay of $$^{100}$$100Mo is found, and a upper limit is set for the half-life of $$0\nu \beta \beta $$0νββ of $$^{100}$$100Mo of $$T^{0\nu }_{1/2} > 9.5\times 10^{22}~\hbox {years}$$T1/20ν>9.5×1022years at 90% C.L. This limit corresponds to an effective Majorana neutrino mass limit in the range $$\langle m_{\beta \beta }\rangle \le (1.2-2.1)\,\hbox {eV}$$⟨mββ⟩≤(1.2-2.1)eV.