The decay chain162Yb (19·0 min) →162Tm (21·8 min) →162Er and the decay of160Tm (9·2 min) TO160Er

The decay of162Yb,162Tm and160Tm has been investigated with Ge(Li) and Si(Li) detectors using isotopically separated samples produced by the YASNAPP facility at Dubna. The singles γ-ray spectrum, β-γ and γ-γ coincidences were measured. Strong ytterbium and thulium activities were used for conversion electron measurements with high resolution magnetic β-spectrographs. 3, 134 and 39 new γ-rays were attributed to the decays of162Yb,162Tm and160Tm, respectively. Decay schemes of these isotopes are proposed. Three and 12 new levels were found in162Er and160Er, respectively. TheQ-values of162Yb,162Tm and160Tm were determined to be ≦2·2, MeV, 4·6±0·3 MeV and 4·9±0·5 MeV, respectively.