First search for $2\varepsilon$ and $\varepsilonβ^+$ decay of $^{174}$Hf

F. A. Danevich; M. Hult; D. V. Kasperovych; G. P. Kovtun; K. V. Kovtun; G. Lutter; G. Marissens; O. G. Polischuk; S. P. Stetsenko; V. I. Tretyak

doi:10.1016/j.nuclphysa.2020.121703

arXiv · 2001.06301

First search for $2\varepsilon$ and $\varepsilonβ^+$ decay of $^{174}$Hf

F. A. Danevich·M. Hult·D. V. Kasperovych·G. P. Kovtun·K. V. Kovtun·G. Lutter·G. Marissens·O. G. Polischuk·S. P. Stetsenko·V. I. Tretyak

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Abstract

The first ever search for $2\varepsilon$ and $\varepsilonβ^+$ decay of $^{174}$Hf was realized using a high-pure sample of hafnium (with mass 179.8 g) and the ultra low-background HPGe-detector system located 225 m underground. After 75 days of data taking no indication of the double beta decay transitions could be detected but lower limits for the half-lives of the different channels and modes of the decays were set on the level of $\lim T_{1/2}\sim 10^{16}-10^{18}$ a.

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F. A. Danevich, M. Hult, D. V. Kasperovych, G. P. Kovtun, K. V. Kovtun, G. Lutter, G. Marissens, O. G. Polischuk, S. P. Stetsenko, V. I. Tretyak. 2020-01-17. First search for $2\varepsilon$ and $\varepsilonβ^+$ decay of $^{174}$Hf. https://doi.org/10.1016/j.nuclphysa.2020.121703

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