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

CdWO4 crystal scintillators from enriched isotopes for double beta decay experiments

Cadmium tungstate crystal scintillators enriched in 106Cd and 116Cd were developed. The produced scintillators exhibit good optical and scintillation properties, and a low level of radioactive contamination. Experiments to search for double beta decay of 106Cd and 116Cd are in progress at the Gran Sasso National Laboratories of the INFN (Italy). Prospects to further improve the radiopurity of the detectors by recrystallization are discussed

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

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

Development of CdWO4 Crystal Scintillators from Enriched Isotopes for 2β-Decay Experiments

Cadmium tungstate crystal scintillators enriched in 106Cd (106CdWO4) and 116Cd (116CdWO4) have been developed to search for 2β-decay of 106Cd and 116Cd

Development of radiopure cadmium tungstate crystal scintillators from enriched 106Cd anD 116Cd to search for double beta decay

Cadmium tungstate crystal scintillators enriched in 106Cd up to 66% (106CdWO4) and in 116Cd up to 82% (116CdWO4) have been developed. The low radioactive contamination of the crystals measured on the level of ≤ 1.5 mBq/kg (40K), ≤ 0.005−0.012 mBq/kg (226Ra), 0.04−0.07 mBq/kg (228Th) allows to carry out high sensitivity experiments to search for double beta processes in 106Cd and 116Cd

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