2015/07/16 by D. Chernyak, Chernyak, Dmitry
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Neutrino Physics Research #Nuclear Experiment (nucl-ex) #Radiation Detection and Scintillator Technologies
paper · pdf · doi:10.48550/arxiv.1507.04591
openalex publication_date 2015/07/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
ZnMoO4 scintillators with a mass of ∼ 0.3 kg, as well as Zn100MoO4 crystals enriched in the isotope 100Mo were produced for the first time by using the low-thermal-gradient Czochralski technique. The optical and luminescent properties of the produced crystals were studied to estimate the progress in crystal growth quality. The low-temperature tests with a 313 g ZnMoO4 and two enriched Zn100MoO4 crystals were performed aboveground in the Centre de Sciences Nucléaires et de Sciences de la Matière. The low background measurements with a three ZnMoO4 and two enriched detectors installed in the EDELWEISS set-up at the Laboratoire Souterrain de Modane were carried out. To optimize the light collection in ZnMoO4 scintillating bolometers, we have simulated the collection of scintillation photons in a detector module for different geometries by Monte Carlo method using the GEANT4 package. Response to the 2ν2β decay of 100Mo was simulated for the enriched Zn100MoO4 detectors of different shape and mass to understand the dependence of 2ν2β decay spectra on crystal shape. We have simulated 48 Zn100MoO4 crystals with a size of Ø60 × 40 mm installed in the EDELWEISS cryostat. The contribution to background from the internal radioactive contamination of the crystals, cosmogenic activation and radioactive contamination of the set-up were simulated. Taking into account poor time resolution of the low temperature bolometers, we also studied contribution to background at the Q2β energy of random coincidences of signals, in particular of 2ν2β decay, which is one of the main sources of background in cryogenic bolometers. Methods of the randomly coinciding events rejection were developed and compared. We have also analyzed dependence of the rejection efficiency on a cryogenic detector performance.