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

Veterinary and sanitary examination of flower honey

Honey is a product of processing by honey bees of nectar or paddy of vegetable or animal origin, which is a sweet aromatic substance or a crystallized mass containing a significant amount of carbohydrates, mineral and biologically active substances The article presents the results of veterinary and sanitary examination and evaluation of five samples of flower honey.The purpose of the study: to determine the quality of honey obtained from apiaries of the Leningrad region in accordance with the "Rules of veterinary and sanitary examination of honey for sale in the markets."The materials for the study were honey samples in the amount of 100 g with a collection date of 2020. For the study, the organoleptic and physico-chemical parameters of honey samples were determined. Organoleptic evaluation was carried out according to the following indicators: color, aroma, taste, consistency, crystallization, determination of signs of fermentation. Physico-chemical parameters: mass fraction of water, presence of oxymethylfurfural, diastase (amylase) activity, determination of total acidity.As a result of organoleptic and physico-chemical studies, it turned out that in sample No. 1 there was an artificial inversion of honey and deviations were found, indicating that honey is not natural.</jats:p

Production of high purity granular metals: cadmium, zinc, lead

Cadmium, zinc and lead are constituent components of many semiconductor compounds. The obtained high purity distillates and ingots are large-size elements, which is not always convenient to use, and thus require additional grinding, which does not always allow maintaining the purity of the original materials. For the growth of semiconductor and scintillation single crystals it is advisable to use "friable" granular high-purity distillates, which can be processed without the risk of contamination. For example, the European low-background experiment LUCIFER required more than 20 kg of high-purity granulated zinc, which was agreed to be supplied by NSC KIPT. This task was then extended to cadmium and lead. Motivated by these tasks, the authors of this paper propose complex processes of deep refining of cadmium, zinc and lead by vacuum distillation. A device producing granules has been developed. The process of granulation of high-purity metals is explored. The purity of produced granules for cadmium and zinc is >99,9999, and >99,9995% for lead granules. To prevent oxidation of metal granules during exposition to air, chemical methods of surface passivation were used. Organic solvent based on dimethylformamide used as a coolant improves the resistance of granules to atmospheric corrosion during the granulation of high purity Cd, Zn and Pb

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

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