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arXiv · 2106.05862

New experimental limits on double-beta decay of osmium

P. Belli·R. Bernabei·F. Cappella·V. Caracciolo·R. Cerulli·F. A. Danevich·A. Incicchitti·D. V. Kasperovych·V. V. Kobychev·G. P. Kovtun·N. G. Kovtun·M. Laubenstein·V. Merlo·D. V. Poda·O. G. Polischuk·A. P. Shcherban·S. Tessalina·V. I. Tretyak
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Abstract

Double-beta processes in $^{184}$Os and $^{192}$Os were searched for over 15851 h at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. by using a 118 g ultra-pure osmium sample installed on the endcap of a 112 cm$^3$ ultra-low-background broad-energy germanium detector. New limits on double-electron capture and electron capture with positron emission in $^{184}$Os were set at the level of $\lim T_{1/2} \sim 10^{16}-10^{17}$ yr. In particular the $2\nu$2K and $2\nu$KL decays of $^{184}$Os to the ground state of $^{184}$W are restricted as $T_{1/2}\geq3.0\times 10^{16}$ yr and $T_{1/2}\geq2.0\times 10^{16}$ yr, respectively. A lower limit on the half-life for the double-beta decay of $^{192}$Os to the first excited level of $^{192}$Pt was set as $\lim T_{1/2}=2.0\times 10^{20}$ yr at 90\% C.L.

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P. Belli, R. Bernabei, F. Cappella, V. Caracciolo, R. Cerulli, F. A. Danevich, A. Incicchitti, D. V. Kasperovych, V. V. Kobychev, G. P. Kovtun, N. G. Kovtun, M. Laubenstein, V. Merlo, D. V. Poda, O. G. Polischuk, A. P. Shcherban, S. Tessalina, V. I. Tretyak. 2021-06-10. New experimental limits on double-beta decay of osmium. https://doi.org/10.1088/1361-6471/ac068a

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