Decay of ¹⁸⁸Re and TRS calculations for its daughter nuclide ¹⁸⁸Os

The γ-ray spectra of ¹⁸⁸Re decay have been studied by using a Compton-suppressed spectrometer and a three parameters γ-γ-T list coincidence system. Experimental data analysis demonstrated that six γ-rays at 557, 810, 1463, 1867, 1936 and 2022 keV and three levels at 1443, 1936 and 2022 keV are confirmed again. Seven new γ-rays at 309.60±0.04, 826.90±0.02, 979.29±0.08, 1103.7±0.4, 1828.2±0.1, 1842.5±0.2 and 1982.5±0.2 keV have been identified, three new levels at 309.60, 1828.2 and 1982.5 keV are assigned. The β^- decay branching ratio is deduced. In addition, in order to study this γ-unstable nucleus, shape calculations using the Hartree–Fock–Bogoliubov-like formalism were carried out for positive-parity states in ¹⁸⁸Os. The TRS plots reveal that, as the spin increases up the band, the triaxiality parameter γ changes. (author)