Next stage of search for 2K(2$ν$)-capture of $^{78}$Kr

Gavriljuk, Ju. M.; Gavrin, V. N.; Gangapshev, A. M.; Kazalov, V. V.; Kuzminov, V. V.; Osetrova, N. Ya.; Pul'nikov, I. I.; Ryabukhin, A. V.; Shubin, A. N.; Skorynin, G. M.; Panasenko, S. I.; Ratkevich, S. S.

Next stage of search for 2K(2$ν$)-capture of $^{78}$Kr

Authors

Description

A technique to search for 2K-capture of $^{78}$Kr with large low-background proportional counter filled with an enriched in $^{78}$Kr up to 99.8% sample of Krypton at a pressure of 4.51 is described in this paper. The results of first measurements are presented. Analysis of data collected during 159 hours yielded new limit to the half-life of $^{78}$Kr with regard to 2K-capture (T$_{1/2}\geq6\cdot10^{21}$ yr (90% C.L.)). Sensitivity of the facility to the process for one year of measurement was evaluated to be $\texttt{S}=1.0\cdot10^{22}$ yr (90% C.L.).
4 pages, 5 figures; talk at the NANP'05 Conference; submitted to Phys. At. Nucl