Double-beta processes in 184Os and 192Os 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 cm3 ultra-low-background broad-energy germanium detector. New limits on double-electron capture and electron capture with positron emission in 184Os were set at the level of limT1/2∼1016−1017 yr. In particular the 2ν2K and 2νKL decays of 184Os to the ground state of 184W are restricted as T1/2≥3.0×1016 yr and T1/2≥2.0×1016 yr, respectively. A lower limit on the half-life for the double-beta decay of 192Os to the first excited level of 192Pt was set as limT1/2=2.0×1020 yr at 90\% C.L.
@article{arxiv.2106.05862,
title = {New experimental limits on double-beta decay of osmium},
author = {P. Belli and R. Bernabei and F. Cappella and V. Caracciolo and R. Cerulli and F. A. Danevich and A. Incicchitti and D. V. Kasperovych and V. V. Kobychev and G. P. Kovtun and N. G. Kovtun and M. Laubenstein and V. Merlo and D. V. Poda and O. G. Polischuk and A. P. Shcherban and S. Tessalina and V. I. Tretyak},
journal= {arXiv preprint arXiv:2106.05862},
year = {2021}
}