0000000000020865
AUTHOR
N. G. Kovtun
Search for2βdecays of96Ru and104Ru by ultralow-background HPGeγspectrometry at LNGS: Final results
An experiment to search for double-$\ensuremath{\beta}$ decay processes in ${}^{96}$Ru and ${}^{104}$Ru, which are accompanied by $\ensuremath{\gamma}$ rays, has been realized in the underground Gran Sasso National Laboratories of the I.N.F.N. (Italy). Ruthenium samples with masses of $\ensuremath{\approx}$0.5--0.7 kg were measured with the help of ultralow-background high-purity Ge $\ensuremath{\gamma}$-ray spectrometry. After 2162 h of data taking the samples were deeply purified to reduce the internal contamination of ${}^{40}$K. The last part of the data has been accumulated over 5479 h. New improved half-life limits on $2{\ensuremath{\beta}}^{+}/\ensuremath{\varepsilon}{\ensuremath{\be…
Searches for neutrinoless resonant double electron captures at LNGS
Several experiments were performed during last years at underground (3600 m w.e.) Laboratori Nazionali del Gran Sasso (LNGS) of the INFN (Italy) to search for resonant 2$\varepsilon0\nu$ captures in 96Ru, 106Cd, 136Ce, 156Dy, 158Dy, 180W, 184Os, 190Pt with the help of HP Ge semiconductor detectors, and ZnWO4 and 106CdWO4 crystal scintillators. No evidence for r-2$\varepsilon0\nu$ decays was found, and only T_{1/2} limits were established in the range of 10^{14}-10^{21} yr.