[en] Measurements of ¹¹⁶Cd double beta decay with help of enriched ¹¹⁶CdWO₄ crystal scintillator are in progress in the Solotvina Underground Laboratory. The last part of the exposition with the background rate less than 0.6 counts/y·kg·keV (in the region of interest 2.7-2.9 MeV) is about 19000 hours. The half-life limit T_1/2(0ν)≥3.2·10²²y (90% C.L.) is obtained for neutrinoless 2β decay of ¹¹⁶Cd. It corresponds to restrictions on the values of the neutrino mass v>≤3.9 eV, right-handed admixtures in weak interaction <η>≤5.7·10^-8, <λ>≤5.0·10^-6 and R-parity violating parameter of minimal supersymmetric standard model ε≤1.1·10^-3. For neutrinoless modes with emission of one and two Majorons, the limits T₍₁₍₂₎₎(0νM1)≥1.2·10²¹ y and T_1/2(0νM2)≥2.4·10²⁰ y (90% C.L.) are determined. To advance these results to a level of the limit v>≤1-2 eV, the improved set-up with four enriched ¹¹⁶CdWO₄ crystals is in mounting now

[en] The experiment was carried out for the research of neutrinoless double beta decay of ₁₀₀Mo with energy release of 3032.6 keV. A sample of molybdenum was used, enriched by the isotope ₁₀₀Mo to 99.5%. The total mass of ₁₀₀Mo was equal to 390 g. A half-life lower limit of >2.1x10₂₁ y for the neutrinoless 2ß-decay at the 68% confidence level mass was established. (author)

[en] A direct experiment searching for the neutrinoless double β decay of ¹³⁰Te is described. A half-life limit equal to 1.2 x 10²¹ years at the 68% confidence level is established. The leptonic charge nonconservation parameter corresponding to this limit is calculated on the basis of a two-nucleon model and found to be (3--5) x 10^-4

[en] The experiment was performed in an underground laboratory located in the Solotvina salt mine at a depth of 430 m below ground level. The germanium-lithium semiconductor detector, 35 cm³ in volume, was shielded with additional layers of mercury, lead, and polyethylene to reduce the background. The background level in the vicinity of the energy of the 2 β decay of ⁷⁶Ge (2040.7 keV) was (1.7 +- 0.5) x 10^-4 counts/h x keV. Processing of the data obtained in 1478 h of measurements made it possible to establish that the halflife of ⁷⁶Ge is longer than 1.1 x 10²² yr at a confidence level of 68%

[en] The experiment was performed at the Solotvina Underground Laboratory with CdWO₄ crystal scintillators enriched in ¹¹⁶Cd to 83%. For the total collection time about 12000 hours the limit of half-life T_1/2^oν ≥ 3.2 centre dot 10²² y (90% CL) was obtained for 0νββ decay of ¹¹⁶ Cd which corresponds to the restriction of the neutrino mass less than 3.9 eV

[en] Results of measurements of the time and spectrometric characteristics of CdS(Te) scintillation crystals produced by advanced technology are presented. The possibility of using detectors based on cadmium sulfide for spectrometry of ionizing radiation at a temperature of 300⁰K is shown. The energy resolution of the better specimens is 21% for the 622-keV ¹³⁷Cs gamma line. Measurements made confirm the possibility of creating spectrometers based on CdS(Te) and allow it to be hoped that cadmium sulfide detectors can be produced that have the necessary parameters of studying ¹¹⁶Cd double beta decay

[en] The measurements with 0.33 kg low background ¹¹⁶CdWO₄ scintillators are in progress in the Solotvina Underground Laboratory. After 13254 h of data taking the new half-life limits for different modes of neutrinoless 2β decay of ¹¹⁶Cd are presented, in particular for 0ν2β decay of ¹¹⁶Cd to the ground state of ¹¹⁶Sn: T_1/2;(0ν2β) ≥ 1.3(1.8) x 10²³ yr at 90%(68%) C.L

[en] Studies of the 2β decay of ¹¹⁶Cd, ¹⁸⁰W and ¹⁸⁶W have been performed in the Solotvina Underground Laboratory with the help of the super-low background ¹¹⁶CdWO₄ crystal scintillators. The half-life value of the two-neutrino 2β decay of ¹¹⁶Cd has been revised as T_1/2^2ν=2.9±0.1(stat)_-0.3^+0.4(syst)x10¹⁹ yr. Besides, the new half-live limits on different modes of this process have been established for two natural tungsten isotopes, in particular, T_1/2≥1.0 (1.6)x10²¹ yr at 90% (68%) C.L. for the neutrinoless 2β decay of ¹⁸⁶W to the ground (0⁺) and first excited (2⁺) level of ¹⁸⁶Os

[en] The new step of the ¹¹⁶Cd 2β-decay experiment is in progress in the Solotvina Underground Laboratory. The upgraded setup consists of 4 enriched ¹¹⁶CdWO₄ crystal scintillators with total mass 339 g. As an active shield, 15 CdWO₄ crystals (20.6 kg) are used. The background rate (in the energy interval 2.7-2.9 MeV) is 0.06 counts/yr keV, one order of magnitude lower than in the previous installation. Combined with results of preceding measurements, the half-life limit for neutronless 2β-decay of ¹¹⁶Cd to ground state of ¹¹⁶Sn is determined as T_1/2(0ν) ν 5.1 x 10²² yr with 90% C.L. The limits on T_1/2 for transitions to excited 2₁⁺ and 0₁⁺ levels of ¹¹⁶Sn are 8.6 x 10²² and 4.1 x 10²¹ yr. respectively (90% C.L.) For 0ν2β-decay with emission of one and two Majorons, the half-life limits are T_1/2(0νM1) ≥ 1.4 x 10²¹ yr and T_1/2(0νM2) ≥ 4.1 x 10¹0²⁰ yr (90% C.L.). Corresponding restrictions on the value of the neutrino mass and the neutrino-Majoron coupling constant are equal to (mν) ≤ 3.1 eV and (g_M) ≤ 1.9 x 10^-4, respectively

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