Search for Rare Nuclear Decays with HPGe Detectors at the STELLA
  Facility of the LNGS
  Results on the search for rare nuclear decays with the ultra low background
facility STELLA at the LNGS using gamma ray spectrometry are presented. In
particular, the best T1/2 limits were obtained for double beta processes in
96Ru and 104Ru. Several isotopes, which potentially decay through different
double beta decay channels, including also possible resonant double electron
captures, were investigated for the first time (156Dy, 158Dy, 184Os, 192Os,
190Pt, 198Pt). Search for resonant absorption of solar 7Li axions in a LiF
crystal gave the best limit for the mass of 7Li axions (< 8.6 keV). Rare alpha
decay of 190Pt to the first excited level of 186Os (Eexc = 137.2 keV) was
observed for the first time.
