Luminescence and Scintillation Response of Ce3+-Doped Oxide Glasses with High Gd2O3 Content

This report presents the luminescence and scintillation response of Ce3+-doped oxide glasses with high Gd2O3 (30 mol%) content. The characteristic emission of Ce3+ 5d → 4f transition peaking around 380 nm was observed in its luminescence spectra under UV and X-ray excitation. Photoluminescence decay kinetics was governed by a few tens of nanoseconds decay time. The integral scintillation efficiency of about 22% of that of the Bi4Ge3O12 scintillator was obtained under X-ray irradiation. The light yield and its dependence on the integration time were measured and compared with that of the Bi4Ge3O12 crystal. The total mass attenuation coefficient at 662 keV γ-rays was also determined and compared with the theoretical one calculated using the WinXCom program.

Luminescence of ZnMoO4 Crystals Developed for the LUMINEU Double Beta Decay Experiment

Scintillation efficiency of ZnMoO4 crystals is one of the main characteristics for application in cryogenic double beta decay experiments. Luminescence of ZnMoO4 crystals developed from deeply purified molybdenum under X-ray irradiation of different doses was studied in the temperature interval from 1.4 K to 295 K. Emission spectra, dependence of luminescence intensity on dose and temperature, phosphorescence and thermally stimulated luminescence were investigated. Two emission bands were identified: recombination luminescence at ~ 600 nm and exciton luminescence at ~ 500 nm. We have found that concentration of shallow traps in the material is much greater than the concentration of deep traps. Furthermore only shallow traps absorb a small part of the luminescence and cause the low scintillation efficiency of the sample.