Decay properties of long-lived isomers in the odd-odd N = 81 nucleus Tb $° {146}$ compared to the Ho $^{148}$ and Tm $^{150}$ nuclei

Excited states of the Tb146 nucleus have been studied using γ-ray and electron spectroscopy in off-beam and in-beam modes following Sn112(Ar40,3n3p) reaction with the use of the OSIRIS-II, HPGe detector array and the conversion electron spectrometer. The multipolarity of the 343 keV transition deexciting the (7−) level in Tb146 shows mainly an E2 nature and the first excited state above the 23 s isomer is assigned as a (5−,6−) state. The log ft values have been deduced for 11 β+/EC transitions populating excited states in Gd146. The systematic behavior of spins and parities of the long-lived levels at 0+x keV and the first excited states above them in the N=81 isotones Tb146, Ho148, and Tm150 is discussed