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Information × Registration Number 0211U009842, 0109U001329 , R & D reports Title Searh for the rare nuclear decays and processes, the decay spectroscopy and nuclear structure popup.stage_title Head Zaliubovsky Illya Ivanovich, Registration Date 30-12-2011 Organization Kharkov National University named after V.N. Karazin popup.description2 The results obtained with the improved experimental setup to search for rare events 2?(2?)-decay of 136Хе and 2К(2?)-capture in 78Kr and 124Хе are represented. With due account taken of the analysis of individual noise characteristic it has been shown that the appropriate choice of both wavelet characteristics and sequence processing algorithms allows one to decrease the background in the energy region of useful events with a unique set of characteristics by ~ 2000 times. New limit on the half-life of 78Kr with regard to 2K-capture for the ground state 78Se(0+?0+,о.с.) was found to be Т??2.4·1021 yrs (90% C.L.). The experimental set-up for investigation 2K-capture in 124Xe was designed and mounted in the low-background underground laboratory of Baksan Neutrino Observatory INR RAS at a depth of 4700 m.w.e. The estimated sensitivity of this set-up to the sought-for process is 1.7·1021 years (95% C.L.) for natural xenon enriched in 124Хе up to 15%. This preliminary result based on data collected during 5200h of live time. Search for 2?-decay of 136Хе is carried out with two high pressure proportional counters and with natural and enriched xenon (93% of 136Хе). The measured half-life is equal to Т?(2?2?)= ·1021yrs. No evidence has been found for neutrinoless 2?-decay. The decay half life limit based on data measured during 13200h is Т? (2?0?)?4.9·1023 yrs (90% C.L.). The ?-decay of around 30 odd nuclei was calculated within the dynamic collective model using expressions for the reduced matrix elements of the weak-interaction Hamiltonian for partial ?-decay obtained earlier by the authors. All of the many-phonon states of the yrast band of an even-even core contributing to the formation of the excited states of nuclei were taken into account. For ?-transitions with an intensity of >1% the calculated log ft values differ from experimental values by no more than 0.2. Product Description popup.authors Дуплій С. Залюбовський І. Ковтун В. Кощій Є. Митрошин В. Раткевич С. Савчук Л. Трубников С. Федорець І. Хлапова Н. popup.nrat_date 2020-04-02 Close