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تسجيل مستخدم جديد2K(2 u)-Capture in Xe-124: Results of Data Processing for an Exposure of 37.7 kg x day
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The results of the experimental search for two-neutrino $2K$-capture in $^{124}$Xe with a large copper proportional counter obtained by processing the data for an exposure of 37.7 kg$times$day are presented. The experimental setup is located at the Underground Low-Background Laboratory of the Baksan Neutrino Observatory at a depth of 4900 m w.e. The combination of methods of selection of useful signals with a unique set of characteristics and the event topology taken into account allowed us to suppress the background in the energy region of interest. A new half-life limit for $2K(2 u)$-capture in $^{124}$Xe was determined: T$_{1/2}geq7.7cdot10^{21}$ yrs (90% C.L.).
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Two-neutrino double electron capture is a process allowed in the Standard Model of Particle Physics. This rare decay has been observed in $^{78}$Kr, $^{130}$Ba and more recently in $^{124}$Xe. In this publication we report on the search for this proc
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