Low background detector with enriched 116CdWO4 crystal scintillators to search for double beta decay of 116Cd

A cadmium tungstate crystal boule enriched in $^{116}$Cd to 82% with mass of 1868 g was grown by the low-thermal-gradient Czochralski technique. The isotopic composition of cadmium and the trace contamination of the crystal were estimated by High Resolution Inductively Coupled Plasma Mass-Spectrometry. The crystal scintillators produced from the boule were subjected to characterization that included measurements of transmittance and energy resolution. A low background scintillation detector with two $^{116}$CdWO$_4$ crystal scintillators (586 g and 589 g) was developed. The detector was running over 1727 h deep underground at the Gran Sasso National Laboratories of the INFN (Italy), which allowed to estimate the radioactive contamination of the enriched crystal scintillators. The radiopurity of a third $^{116}$CdWO$_4$ sample (326 g) was tested with the help of ultra-low background high purity germanium $\gamma$ detector. Monte Carlo simulations of double $\beta$ processes in $^{116}$Cd were used to estimate the sensitivity of an experiment to search for double $\beta$ decay of $^{116}$Cd.Comment: 24 pages, 13 figures, 3 tables, accepted for publication on Journal of Instrumentatio

Tungstate and Molybdate Scintillators to Search for Dark Matter and Double Beta Decay

Results are presented on our latest research, aimed at the development and study of oxide scintillation crystals (ZnWO4, ZnMoO4, PbWO4, PbMoO4, and MgWO4) with high scintillation yield and low intrinsic radioactivity. We report on the improvement of these properties for conventional scintillators, as well as on new promising crystals based on metal tungstates and molybdates. The results are discussed in view of applying these materials in cryogenic experiments searching for dark matter and/or neutrinoless double beta decay. © 2006 IEEE

First Results of the Experiment to Search for 2beta Decay of 106Cd with the Help of 106CdWO4 Crystal Scintillators

First Results of the Experiment to Search for 2beta Decay of 106Cd with the Help of 106CdWO4 Crystal Scintillators are presente

First results of the experiment to search for 2β decay of 106Cd with the help of 106CdWO4 crystal scintillators

An experiment to search for 2β processes in 106Cd with the help of 106CdWO4 crystal scintillator (mass of 215 g), enriched in 106Cd up to 66 %, is in progress at the Gran Sasso National Laboratories of the INFN (Italy). After 1320 h of data taking, limits on double beta processes in 106Cd have been established on the level of 1019 − 1020 yr, in particular (all the results at 90 % C.L.): T1/2(0ν2ε) > 3.6 · 1020 yr, T1/2(2νεβ+) > 7.2 · 1019 yr, and T1/2(2ν2β+) > 2.5 · 1020 yr. Resonant 0ν2ε processes have been restricted as T1/2(0ν2K) > 1.4 · 1020 yr and T1/2(0νLK) > 3.2 · 1020 yr. A possible resonant enhancement of the 0ν2ε processes is estimated in the framework of the QRPA approach

EURECA – setting the scene for scintillators

voir fichier complet des proceedingsInternational audienceEURECA (European Underground Rare Event Calorimeter Array) will be an astro-particle physics facility aiming to directly detect galactic dark matter. TheLaboratoire Souterrain de Modane has been selected as host laboratory. TheEURECA collaboration concentrates effort on cryogenic detector research inEurope into a single facility by bringing together colleagues from CRESST,EDELWEISS, ROSEBUD and additional new member institutes. EURECA will use atarget mass of up to one ton for exploring WIMP-nucleon scalar scattering crosssections in the region of 10 −9 – 10 −10 picobarn. A major advantage of EURECAis the planned use of more than just one target material (multi targetexperiment for WIMP identification)

Double beta experiments with the help of scintillation and HPGe detectors at Gran Sasso

A search for double beta decay of 64,70Zn, 180,186W was carried out by using low background ZnWO4 crystal scintillators while a CeCl3 scintillation detector was applied to investigate 2β processes in 136,138,142Ce. A search for 2β decay of 96,104Ru, 156,158Dy, 190,198Pt and study of 2ν2β decay of 100Mo to the first excited 0+ level of 100Ru were realized by ultra‐low background HPGe γ spectrometry. Moreover CdWO4 crystal scintillators from enriched 106Cd and 116Cd isotopes were developed to search for 2β decay of 106Cd and 116Cd. Finally experiments aimed to investigate 96,104Ru and 116Cd are in progress and a new phase of the experiment to search for 2β processes in 106Cd is in preparation