Levels of 186W from the Decay of 186Ta

Abstract
Gamma rays from the decay of 10.5 min 186Ta have been studied using high resolution Ge(Li) detectors. More than 90 gamma rays have been observed. Several photo-peaks previously reported as single lines were found to be close doublets. The results of this study have been correlated with the published γ–γ coincidence data and the recent (d,d′) reaction work and a decay scheme for 186Ta has been constructed. The scheme incorporates more than 85 transitions among 23 excited states in 186W. The level at 1661 keV has been discussed in terms of a two-proton quasi-particle state arising from the Nilsson orbitals Ωπ[NnzΛ] = 7/2+[404] and 1/2+[411]. Several transition probabilities have been extracted and compared with other recent experimental data and with the calculations of Kumar and Baranger as well as with the predictions of various phenomenological models.